feat: add repository workspace as default project view

- Create git file utilities (list_tree, get_file_content, list_branches, commit_file)
- Add file browsing API endpoints (list, content, branches, update)
- Create RepoWorkspace page with sidebar + main content layout
- Add FileTree component with directory navigation
- Add FileViewer component for viewing file contents
- Update project list to link to workspace
- Add workspace CSS styles
- Update router with workspace route

Quality gates: ruff ✓, mypy ✓, typecheck ✓, build ✓

apps/api/src/api/git_repositories.py

@@ -14,6 +14,12 @@ from src.config import Settings
 from src.models.git_repository import GitRepository
 from src.models.project import Project
 from src.models.user import User
+from src.utils.git_files import (
+    commit_file,
+    get_file_content,
+    list_branches,
+    list_tree,
+)
 from src.utils.git_history import get_commit_detail, get_commit_history
 from src.utils.git_url_parser import parse_git_url
 
@@ -265,3 +271,198 @@ async def get_repository_commit(
         return detail
     except (RuntimeError, ValueError) as e:
         raise HTTPException(status_code=status.HTTP_400_BAD_REQUEST, detail=str(e))
+
+
+# File browsing endpoints
+
+
+class FileListResponse(BaseModel):
+    path: str
+    branch: str
+    entries: list[dict]
+
+
+class FileContentResponse(BaseModel):
+    path: str
+    branch: str
+    content: str
+    size: int
+    encoding: str
+    language: str | None
+    is_binary: bool
+    last_commit: dict | None
+
+
+class BranchesResponse(BaseModel):
+    branches: list[dict]
+    default_branch: str
+
+
+class FileUpdateRequest(BaseModel):
+    path: str
+    branch: str
+    content: str
+    commit_message: str
+
+
+class FileUpdateResponse(BaseModel):
+    commit_hash: str
+    message: str
+    branch: str
+
+
+@router.get("/{project_id}/repositories/{repo_id}/files", response_model=FileListResponse)
+async def list_repository_files(
+    project_id: uuid.UUID,
+    repo_id: uuid.UUID,
+    branch: str = "main",
+    path: str = "",
+    user_id: uuid.UUID = Depends(get_current_user_id),
+    session: AsyncSession = Depends(get_db_session),
+) -> FileListResponse:
+    """List files and directories in a repository path."""
+    _user = await _get_user(session, user_id)
+    _project = await _get_owned_project(project_id, user_id, session)
+
+    repo = await session.get(GitRepository, repo_id)
+    if repo is None or repo.project_id != project_id:
+        raise HTTPException(status_code=status.HTTP_404_NOT_FOUND, detail="repository not found")
+
+    if not os.path.exists(repo.path):
+        raise HTTPException(status_code=status.HTTP_404_NOT_FOUND, detail="repository not found on disk")
+
+    try:
+        entries = list_tree(repo.path, branch=branch, path=path)
+        return FileListResponse(
+            path=path,
+            branch=branch,
+            entries=[
+                {
+                    "name": e.name,
+                    "type": e.type,
+                    "path": e.path,
+                    "size": e.size,
+                    "mode": e.mode,
+                    "last_commit": e.last_commit,
+                }
+                for e in entries
+            ],
+        )
+    except RuntimeError as e:
+        raise HTTPException(status_code=status.HTTP_400_BAD_REQUEST, detail=str(e))
+
+
+@router.get("/{project_id}/repositories/{repo_id}/files/content", response_model=FileContentResponse)
+async def get_repository_file_content(
+    project_id: uuid.UUID,
+    repo_id: uuid.UUID,
+    branch: str,
+    path: str,
+    user_id: uuid.UUID = Depends(get_current_user_id),
+    session: AsyncSession = Depends(get_db_session),
+) -> FileContentResponse:
+    """Get the content of a file."""
+    _user = await _get_user(session, user_id)
+    _project = await _get_owned_project(project_id, user_id, session)
+
+    repo = await session.get(GitRepository, repo_id)
+    if repo is None or repo.project_id != project_id:
+        raise HTTPException(status_code=status.HTTP_404_NOT_FOUND, detail="repository not found")
+
+    if not os.path.exists(repo.path):
+        raise HTTPException(status_code=status.HTTP_404_NOT_FOUND, detail="repository not found on disk")
+
+    try:
+        file_content = get_file_content(repo.path, branch=branch, path=path)
+        return FileContentResponse(
+            path=file_content.path,
+            branch=file_content.branch,
+            content=file_content.content,
+            size=file_content.size,
+            encoding=file_content.encoding,
+            language=file_content.language,
+            is_binary=file_content.is_binary,
+            last_commit=file_content.last_commit,
+        )
+    except FileNotFoundError:
+        raise HTTPException(status_code=status.HTTP_404_NOT_FOUND, detail="file not found")
+    except RuntimeError as e:
+        raise HTTPException(status_code=status.HTTP_400_BAD_REQUEST, detail=str(e))
+
+
+@router.get("/{project_id}/repositories/{repo_id}/branches", response_model=BranchesResponse)
+async def get_repository_branches(
+    project_id: uuid.UUID,
+    repo_id: uuid.UUID,
+    user_id: uuid.UUID = Depends(get_current_user_id),
+    session: AsyncSession = Depends(get_db_session),
+) -> BranchesResponse:
+    """List all branches in the repository."""
+    _user = await _get_user(session, user_id)
+    _project = await _get_owned_project(project_id, user_id, session)
+
+    repo = await session.get(GitRepository, repo_id)
+    if repo is None or repo.project_id != project_id:
+        raise HTTPException(status_code=status.HTTP_404_NOT_FOUND, detail="repository not found")
+
+    if not os.path.exists(repo.path):
+        raise HTTPException(status_code=status.HTTP_404_NOT_FOUND, detail="repository not found on disk")
+
+    try:
+        branches, default_branch = list_branches(repo.path)
+        return BranchesResponse(
+            branches=[
+                {
+                    "name": b.name,
+                    "is_default": b.is_default,
+                    "last_commit": b.last_commit,
+                }
+                for b in branches
+            ],
+            default_branch=default_branch,
+        )
+    except RuntimeError as e:
+        raise HTTPException(status_code=status.HTTP_400_BAD_REQUEST, detail=str(e))
+
+
+@router.post("/{project_id}/repositories/{repo_id}/files/content", response_model=FileUpdateResponse)
+async def update_repository_file(
+    project_id: uuid.UUID,
+    repo_id: uuid.UUID,
+    data: FileUpdateRequest,
+    user_id: uuid.UUID = Depends(get_current_user_id),
+    session: AsyncSession = Depends(get_db_session),
+) -> FileUpdateResponse:
+    """Update a file and create a commit."""
+    _user = await _get_user(session, user_id)
+    _project = await _get_owned_project(project_id, user_id, session)
+
+    repo = await session.get(GitRepository, repo_id)
+    if repo is None or repo.project_id != project_id:
+        raise HTTPException(status_code=status.HTTP_404_NOT_FOUND, detail="repository not found")
+
+    if not os.path.exists(repo.path):
+        raise HTTPException(status_code=status.HTTP_404_NOT_FOUND, detail="repository not found on disk")
+
+    # Get user info for commit
+    user = await _get_user(session, user_id)
+    author_name = user.name or "Unknown"
+    author_email = user.email or "unknown@example.com"
+
+    try:
+        commit_hash = commit_file(
+            repo_path=repo.path,
+            branch=data.branch,
+            path=data.path,
+            content=data.content,
+            commit_message=data.commit_message,
+            author_name=author_name,
+            author_email=author_email,
+        )
+        return FileUpdateResponse(
+            commit_hash=commit_hash,
+            message=data.commit_message,
+            branch=data.branch,
+        )
+    except RuntimeError as e:
+        raise HTTPException(status_code=status.HTTP_400_BAD_REQUEST, detail=str(e))

apps/api/src/utils/git_files.py

@@ -0,0 +1,391 @@
+"""Git file utilities for browsing repository contents."""
+
+import subprocess
+from dataclasses import dataclass
+from pathlib import Path
+from typing import Any
+
+
+@dataclass
+class FileTreeEntry:
+    """Represents a file or directory in the repository."""
+
+    name: str
+    type: str  # "file" or "directory"
+    path: str
+    size: int | None = None
+    mode: str | None = None
+    last_commit: dict[str, Any] | None = None
+
+
+@dataclass
+class BranchInfo:
+    """Represents a git branch."""
+
+    name: str
+    is_default: bool
+    last_commit: dict[str, Any] | None = None
+
+
+@dataclass
+class FileContent:
+    """Represents file content and metadata."""
+
+    path: str
+    branch: str
+    content: str
+    size: int
+    encoding: str
+    language: str | None
+    is_binary: bool
+    last_commit: dict[str, Any] | None = None
+
+
+def _run_git_command(repo_path: str, *args: str) -> str:
+    """Run a git command in the repository directory."""
+    result = subprocess.run(
+        ["git", *args],
+        cwd=repo_path,
+        capture_output=True,
+        text=True,
+    )
+    if result.returncode != 0:
+        raise RuntimeError(f"Git command failed: {result.stderr}")
+    return result.stdout
+
+
+def list_tree(repo_path: str, branch: str = "main", path: str = "") -> list[FileTreeEntry]:
+    """List files and directories in a repository path.
+
+    Args:
+        repo_path: Path to the git repository
+        branch: Branch name to list from
+        path: Directory path within the repository (empty for root)
+
+    Returns:
+        List of FileTreeEntry objects
+    """
+    tree_path = f"{branch}:{path}" if path else branch
+
+    try:
+        output = _run_git_command(repo_path, "ls-tree", "-l", tree_path)
+    except RuntimeError:
+        # Try with HEAD if branch doesn't exist
+        tree_path = f"HEAD:{path}" if path else "HEAD"
+        output = _run_git_command(repo_path, "ls-tree", "-l", tree_path)
+
+    entries = []
+    for line in output.strip().split("\n"):
+        if not line:
+            continue
+
+        # Format: <mode> <type> <hash> <size>\t<name>
+        parts = line.split("\t", 1)
+        if len(parts) != 2:
+            continue
+
+        meta, name = parts
+        meta_parts = meta.split()
+        if len(meta_parts) < 4:
+            continue
+
+        mode = meta_parts[0]
+        obj_type = meta_parts[1]
+        _ = meta_parts[2]  # object hash, not used
+        size = int(meta_parts[3]) if obj_type == "blob" else None
+
+        entry_path = f"{path}/{name}" if path else name
+
+        # Get last commit info for this entry
+        last_commit = _get_last_commit_for_path(repo_path, branch, entry_path)
+
+        entries.append(
+            FileTreeEntry(
+                name=name,
+                type="directory" if obj_type == "tree" else "file",
+                path=entry_path,
+                size=size,
+                mode=mode,
+                last_commit=last_commit,
+            )
+        )
+
+    return entries
+
+
+def _get_last_commit_for_path(repo_path: str, branch: str, path: str) -> dict[str, Any] | None:
+    """Get the last commit that modified a path."""
+    try:
+        output = _run_git_command(
+            repo_path,
+            "log",
+            "-1",
+            "--format=%H|%s|%an|%aI",
+            branch,
+            "--",
+            path,
+        )
+        if not output.strip():
+            return None
+
+        parts = output.strip().split("|", 3)
+        if len(parts) != 4:
+            return None
+
+        return {
+            "hash": parts[0],
+            "message": parts[1],
+            "author": parts[2],
+            "date": parts[3],
+        }
+    except RuntimeError:
+        return None
+
+
+def get_file_content(repo_path: str, branch: str, path: str) -> FileContent:
+    """Get the content of a file.
+
+    Args:
+        repo_path: Path to the git repository
+        branch: Branch name
+        path: File path within the repository
+
+    Returns:
+        FileContent with content and metadata
+    """
+    # Check if file exists
+    try:
+        _run_git_command(repo_path, "cat-file", "-e", f"{branch}:{path}")
+    except RuntimeError:
+        raise FileNotFoundError(f"File '{path}' not found in branch '{branch}'")
+
+    # Get file size
+    size_output = _run_git_command(repo_path, "cat-file", "-s", f"{branch}:{path}")
+    size = int(size_output.strip())
+
+    # Check if binary
+    is_binary = _is_binary_file(repo_path, branch, path)
+
+    # Get content (only for text files)
+    content = ""
+    if not is_binary:
+        content = _run_git_command(repo_path, "show", f"{branch}:{path}")
+
+    # Detect language from extension
+    language = _detect_language(path)
+
+    # Get last commit
+    last_commit = _get_last_commit_for_path(repo_path, branch, path)
+
+    return FileContent(
+        path=path,
+        branch=branch,
+        content=content,
+        size=size,
+        encoding="utf-8",
+        language=language,
+        is_binary=is_binary,
+        last_commit=last_commit,
+    )
+
+
+def _is_binary_file(repo_path: str, branch: str, path: str) -> bool:
+    """Check if a file is binary."""
+    try:
+        _run_git_command(
+            repo_path,
+            "diff",
+            "--numstat",
+            "--",
+            path,
+        )
+        # Alternative: use git show and check for null bytes
+        content = _run_git_command(repo_path, "show", f"{branch}:{path}")
+        return b"\x00" in content.encode("utf-8", errors="replace")
+    except RuntimeError:
+        return True
+
+
+def _detect_language(path: str) -> str | None:
+    """Detect programming language from file extension."""
+    ext = Path(path).suffix.lower()
+    language_map = {
+        ".py": "python",
+        ".js": "javascript",
+        ".ts": "typescript",
+        ".jsx": "jsx",
+        ".tsx": "tsx",
+        ".html": "html",
+        ".css": "css",
+        ".scss": "scss",
+        ".json": "json",
+        ".md": "markdown",
+        ".yaml": "yaml",
+        ".yml": "yaml",
+        ".sh": "bash",
+        ".rs": "rust",
+        ".go": "go",
+        ".java": "java",
+        ".c": "c",
+        ".cpp": "cpp",
+        ".h": "c",
+        ".php": "php",
+        ".rb": "ruby",
+        ".sql": "sql",
+        ".dockerfile": "dockerfile",
+        ".vue": "vue",
+        ".svelte": "svelte",
+    }
+    return language_map.get(ext)
+
+
+def list_branches(repo_path: str) -> tuple[list[BranchInfo], str]:
+    """List all branches and identify the default branch.
+
+    Args:
+        repo_path: Path to the git repository
+
+    Returns:
+        Tuple of (list of BranchInfo, default branch name)
+    """
+    # Get all branches
+    output = _run_git_command(repo_path, "branch", "-a", "--format=%(refname:short)")
+
+    branches: list[BranchInfo] = []
+    default_branch = "main"
+
+    for line in output.strip().split("\n"):
+        if not line:
+            continue
+
+        branch_name = line.strip()
+        # Skip remote tracking branches (they start with remotes/)
+        if branch_name.startswith("remotes/"):
+            # Extract just the branch name part
+            parts = branch_name.split("/", 2)
+            if len(parts) >= 3:
+                branch_name = parts[2]
+            else:
+                continue
+
+        # Skip duplicates
+        if any(b.name == branch_name for b in branches):
+            continue
+
+        # Check if this is the default branch (HEAD points to it)
+        try:
+            head_output = _run_git_command(
+                repo_path,
+                "symbolic-ref",
+                "HEAD",
+            )
+            if head_output.strip() == f"refs/heads/{branch_name}":
+                default_branch = branch_name
+        except RuntimeError:
+            pass
+
+        # Get last commit for branch
+        last_commit = _get_last_commit_for_path(repo_path, branch_name, ".")
+
+        branches.append(
+            BranchInfo(
+                name=branch_name,
+                is_default=(branch_name == default_branch),
+                last_commit=last_commit,
+            )
+        )
+
+    # If no branches found, try to get HEAD
+    if not branches:
+        try:
+            output = _run_git_command(repo_path, "rev-parse", "--abbrev-ref", "HEAD")
+            branch_name = output.strip()
+            if branch_name and branch_name != "HEAD":
+                last_commit = _get_last_commit_for_path(repo_path, branch_name, ".")
+                branches.append(
+                    BranchInfo(
+                        name=branch_name,
+                        is_default=True,
+                        last_commit=last_commit,
+                    )
+                )
+                default_branch = branch_name
+        except RuntimeError:
+            pass
+
+    return branches, default_branch
+
+
+def commit_file(
+    repo_path: str,
+    branch: str,
+    path: str,
+    content: str,
+    commit_message: str,
+    author_name: str,
+    author_email: str,
+) -> str:
+    """Commit a file change.
+
+    Args:
+        repo_path: Path to the git repository
+        branch: Branch to commit to
+        path: File path within the repository
+        content: New file content
+        commit_message: Commit message
+        author_name: Author name
+        author_email: Author email
+
+    Returns:
+        Commit hash
+    """
+    # For bare repositories, we need to use git commands differently
+    # We'll create a temporary worktree, make changes, and commit
+
+    import tempfile
+    import os
+
+    # Create a temporary worktree
+    with tempfile.TemporaryDirectory() as worktree_path:
+        # Add worktree
+        _run_git_command(
+            repo_path,
+            "worktree",
+            "add",
+            "--detach",
+            worktree_path,
+            branch,
+        )
+
+        try:
+            # Write file content
+            file_path = os.path.join(worktree_path, path)
+            os.makedirs(os.path.dirname(file_path), exist_ok=True)
+            with open(file_path, "w", encoding="utf-8") as f:
+                f.write(content)
+
+            # Configure git author
+            _run_git_command(worktree_path, "config", "user.name", author_name)
+            _run_git_command(worktree_path, "config", "user.email", author_email)
+
+            # Stage and commit
+            _run_git_command(worktree_path, "add", path)
+            _run_git_command(
+                worktree_path,
+                "commit",
+                "-m",
+                commit_message,
+            )
+
+            # Get commit hash
+            commit_hash = _run_git_command(
+                worktree_path,
+                "rev-parse",
+                "HEAD",
+            ).strip()
+
+            return commit_hash
+
+        finally:
+            # Remove worktree
+            _run_git_command(repo_path, "worktree", "remove", worktree_path)

apps/web/src/pages/projects.tsx

@@ -136,8 +136,8 @@ export const ProjectsPage = () => {
                 {project.description && <p className="muted">{project.description}</p>}
               </div>
               <div className="project-actions">
-                <Link className="ghost-button" to={`/projects/${project.id}/repositories`}>
+                <Link className="ghost-button" to={`/projects/${project.id}`}>
-                  Repositories
+                  Open Workspace
                 </Link>
                 <button
                   className="ghost-button"

apps/web/src/pages/repo-workspace.tsx

@@ -0,0 +1,323 @@
+import { useCallback, useEffect, useState } from "react";
+
+import { Link, useNavigate, useParams, useSearchParams } from "react-router-dom";
+
+import { listRepositories, type GitRepository } from "../api/git_repositories";
+
+type WorkspaceStatus = "loading" | "ready" | "error" | "empty";
+
+export const RepoWorkspace = () => {
+  const { projectId } = useParams<{ projectId: string }>();
+  const [searchParams, setSearchParams] = useSearchParams();
+  const navigate = useNavigate();
+
+  const [status, setStatus] = useState<WorkspaceStatus>("loading");
+  const [repositories, setRepositories] = useState<GitRepository[]>([]);
+  const [selectedRepoId, setSelectedRepoId] = useState<string | null>(
+    searchParams.get("repo")
+  );
+
+  const loadRepositories = useCallback(async () => {
+    if (!projectId) return;
+
+    setStatus("loading");
+    try {
+      const data = await listRepositories(projectId);
+      setRepositories(data);
+
+      if (data.length === 0) {
+        setStatus("empty");
+      } else {
+        setStatus("ready");
+        // If no repo selected, select the first one
+        if (!selectedRepoId) {
+          setSelectedRepoId(data[0].id);
+          const newParams = new URLSearchParams(searchParams);
+          newParams.set("repo", data[0].id);
+          setSearchParams(newParams, { replace: true });
+        }
+      }
+    } catch {
+      setRepositories([]);
+      setStatus("error");
+    }
+  }, [projectId, selectedRepoId, searchParams, setSearchParams]);
+
+  useEffect(() => {
+    void loadRepositories();
+  }, [loadRepositories]);
+
+  const handleRepoChange = (repoId: string) => {
+    setSelectedRepoId(repoId);
+    const newParams = new URLSearchParams(searchParams);
+    newParams.set("repo", repoId);
+    newParams.delete("branch");
+    newParams.delete("path");
+    setSearchParams(newParams);
+  };
+
+  const selectedRepo = repositories.find((r) => r.id === selectedRepoId);
+
+  return (
+    <section className="repo-workspace">
+      <div className="workspace-header">
+        <div className="workspace-title">
+          <h1>Repository Workspace</h1>
+          {selectedRepo && <span className="repo-name">{selectedRepo.name}</span>}
+        </div>
+        <div className="workspace-actions">
+          <Link
+            className="secondary-button"
+            to={`/projects/${projectId}/repositories`}
+          >
+            Manage Repositories
+          </Link>
+        </div>
+      </div>
+
+      {status === "loading" && (
+        <p className="muted">Loading repositories...</p>
+      )}
+
+      {status === "error" && (
+        <div className="card stack">
+          <p>Failed to load repositories</p>
+          <button
+            className="secondary-button"
+            onClick={() => void loadRepositories()}
+            type="button"
+          >
+            Retry
+          </button>
+        </div>
+      )}
+
+      {status === "empty" && (
+        <div className="card stack">
+          <p>No repositories in this project yet.</p>
+          <Link
+            className="primary-button"
+            to={`/projects/${projectId}/repositories`}
+          >
+            Add Repository
+          </Link>
+        </div>
+      )}
+
+      {status === "ready" && repositories.length > 0 && (
+        <div className="workspace-layout">
+          <aside className="workspace-sidebar">
+            <div className="sidebar-section">
+              <label className="form-field">
+                Repository
+                <select
+                  value={selectedRepoId || ""}
+                  onChange={(e) => handleRepoChange(e.target.value)}
+                >
+                  {repositories.map((repo) => (
+                    <option key={repo.id} value={repo.id}>
+                      {repo.name}
+                    </option>
+                  ))}
+                </select>
+              </label>
+            </div>
+
+            {selectedRepoId && (
+              <FileBrowser
+                projectId={projectId!}
+                repoId={selectedRepoId}
+              />
+            )}
+          </aside>
+
+          <main className="workspace-main">
+            {selectedRepoId && (
+              <FileViewer projectId={projectId!} repoId={selectedRepoId} />
+            )}
+          </main>
+        </div>
+      )}
+    </section>
+  );
+};
+
+// File Browser Component
+const FileBrowser = ({
+  projectId,
+  repoId,
+}: {
+  projectId: string;
+  repoId: string;
+}) => {
+  const [searchParams, setSearchParams] = useSearchParams();
+  const [entries, setEntries] = useState<any[]>([]);
+  const [loading, setLoading] = useState(true);
+  const [error, setError] = useState<string | null>(null);
+
+  const branch = searchParams.get("branch") || "main";
+  const path = searchParams.get("path") || "";
+
+  const loadFiles = useCallback(async () => {
+    setLoading(true);
+    setError(null);
+    try {
+      const response = await fetch(
+        `/api/projects/${projectId}/repositories/${repoId}/files?branch=${encodeURIComponent(
+          branch
+        )}&path=${encodeURIComponent(path)}`,
+        { credentials: "include" }
+      );
+      if (!response.ok) {
+        throw new Error("Failed to load files");
+      }
+      const data = await response.json();
+      setEntries(data.entries || []);
+    } catch {
+      setError("Failed to load files");
+    } finally {
+      setLoading(false);
+    }
+  }, [projectId, repoId, branch, path]);
+
+  useEffect(() => {
+    void loadFiles();
+  }, [loadFiles]);
+
+  const handleEntryClick = (entry: any) => {
+    if (entry.type === "directory") {
+      const newParams = new URLSearchParams(searchParams);
+      newParams.set("path", entry.path);
+      setSearchParams(newParams);
+    } else {
+      const newParams = new URLSearchParams(searchParams);
+      newParams.set("file", entry.path);
+      setSearchParams(newParams);
+    }
+  };
+
+  const navigateUp = () => {
+    if (!path) return;
+    const parentPath = path.split("/").slice(0, -1).join("/");
+    const newParams = new URLSearchParams(searchParams);
+    if (parentPath) {
+      newParams.set("path", parentPath);
+    } else {
+      newParams.delete("path");
+    }
+    setSearchParams(newParams);
+  };
+
+  if (loading) return <p className="muted">Loading files...</p>;
+  if (error) return <p className="error-text">{error}</p>;
+
+  return (
+    <div className="file-tree">
+      {path && (
+        <button className="tree-entry tree-up" onClick={navigateUp} type="button">
+          📁 ..
+        </button>
+      )}
+      {entries.map((entry) => (
+        <button
+          key={entry.path}
+          className={`tree-entry ${entry.type === "directory" ? "tree-directory" : "tree-file"}`}
+          onClick={() => handleEntryClick(entry)}
+          type="button"
+        >
+          {entry.type === "directory" ? "📁" : "📄"} {entry.name}
+        </button>
+      ))}
+    </div>
+  );
+};
+
+// File Viewer Component
+const FileViewer = ({
+  projectId,
+  repoId,
+}: {
+  projectId: string;
+  repoId: string;
+}) => {
+  const [searchParams, setSearchParams] = useSearchParams();
+  const [content, setContent] = useState<string | null>(null);
+  const [loading, setLoading] = useState(false);
+  const [error, setError] = useState<string | null>(null);
+  const [isBinary, setIsBinary] = useState(false);
+
+  const branch = searchParams.get("branch") || "main";
+  const filePath = searchParams.get("file");
+
+  const loadFile = useCallback(async () => {
+    if (!filePath) {
+      setContent(null);
+      return;
+    }
+
+    setLoading(true);
+    setError(null);
+    try {
+      const response = await fetch(
+        `/api/projects/${projectId}/repositories/${repoId}/files/content?branch=${encodeURIComponent(
+          branch
+        )}&path=${encodeURIComponent(filePath)}`,
+        { credentials: "include" }
+      );
+      if (!response.ok) {
+        throw new Error("Failed to load file");
+      }
+      const data = await response.json();
+      if (data.is_binary) {
+        setIsBinary(true);
+        setContent("Binary file - cannot display");
+      } else {
+        setIsBinary(false);
+        setContent(data.content);
+      }
+    } catch {
+      setError("Failed to load file");
+    } finally {
+      setLoading(false);
+    }
+  }, [projectId, repoId, branch, filePath]);
+
+  useEffect(() => {
+    void loadFile();
+  }, [loadFile]);
+
+  if (!filePath) {
+    return (
+      <div className="file-viewer-empty">
+        <p className="muted">Select a file to view its contents</p>
+      </div>
+    );
+  }
+
+  if (loading) return <p className="muted">Loading file...</p>;
+  if (error) return <p className="error-text">{error}</p>;
+
+  return (
+    <div className="file-viewer">
+      <div className="file-viewer-header">
+        <div className="file-breadcrumbs">
+          {filePath.split("/").map((part, i, arr) => (
+            <span key={i}>
+              {part}
+              {i < arr.length - 1 && <span className="breadcrumb-sep">/</span>}
+            </span>
+          ))}
+        </div>
+      </div>
+      <div className="file-content">
+        {isBinary ? (
+          <p className="muted">{content}</p>
+        ) : (
+          <pre>
+            <code>{content}</code>
+          </pre>
+        )}
+      </div>
+    </div>
+  );
+};

apps/web/src/router.tsx

@@ -8,6 +8,7 @@ import { ProfilePage } from "./pages/profile";
 import { ProjectsPage } from "./pages/projects";
 import { GitRepositoriesPage } from "./pages/git-repositories";
 import { GitHistoryPage } from "./pages/git-history";
+import { RepoWorkspace } from "./pages/repo-workspace";
 import { SSHKeysPage } from "./pages/ssh-keys";
 import { SettingsPage } from "./pages/settings";
 import { ToolTypesPage } from "./pages/tool-types";
@@ -26,6 +27,7 @@ export const AppRouter = () => {
       >
         <Route index element={<DashboardPage />} />
         <Route path="projects" element={<ProjectsPage />} />
+        <Route path="projects/:projectId" element={<RepoWorkspace />} />
         <Route path="projects/:projectId/repositories" element={<GitRepositoriesPage />} />
         <Route path="projects/:projectId/repositories/:repoId/history" element={<GitHistoryPage />} />
         <Route path="ssh-keys" element={<SSHKeysPage />} />

apps/web/src/styles.css

@@ -694,3 +694,151 @@ a {
     top: 1rem;
   }
 }
+
+/* Repository Workspace */
+.repo-workspace {
+  display: flex;
+  flex-direction: column;
+  height: calc(100vh - 60px);
+  overflow: hidden;
+}
+
+.workspace-header {
+  display: flex;
+  justify-content: space-between;
+  align-items: center;
+  padding: 1rem;
+  border-bottom: 1px solid var(--border);
+  background: var(--panel);
+}
+
+.workspace-title {
+  display: flex;
+  align-items: center;
+  gap: 1rem;
+}
+
+.workspace-title h1 {
+  margin: 0;
+  font-size: 1.25rem;
+}
+
+.repo-name {
+  color: var(--muted);
+  font-size: 0.875rem;
+}
+
+.workspace-layout {
+  display: flex;
+  flex: 1;
+  overflow: hidden;
+}
+
+.workspace-sidebar {
+  width: 280px;
+  min-width: 280px;
+  border-right: 1px solid var(--border);
+  background: var(--panel);
+  display: flex;
+  flex-direction: column;
+  overflow: hidden;
+}
+
+.sidebar-section {
+  padding: 1rem;
+  border-bottom: 1px solid var(--border);
+}
+
+.sidebar-section label {
+  margin: 0;
+}
+
+.workspace-main {
+  flex: 1;
+  overflow: auto;
+  padding: 1rem;
+  background: var(--bg);
+}
+
+/* File Tree */
+.file-tree {
+  flex: 1;
+  overflow: auto;
+  padding: 0.5rem;
+}
+
+.tree-entry {
+  display: block;
+  width: 100%;
+  padding: 0.375rem 0.5rem;
+  border: none;
+  background: none;
+  color: var(--ink);
+  text-align: left;
+  cursor: pointer;
+  border-radius: 4px;
+  font-size: 0.875rem;
+  white-space: nowrap;
+  overflow: hidden;
+  text-overflow: ellipsis;
+}
+
+.tree-entry:hover {
+  background: var(--bg);
+}
+
+.tree-directory {
+  font-weight: 500;
+}
+
+.tree-up {
+  color: var(--muted);
+  font-style: italic;
+}
+
+/* File Viewer */
+.file-viewer {
+  background: var(--panel);
+  border: 1px solid var(--border);
+  border-radius: 8px;
+  overflow: hidden;
+}
+
+.file-viewer-header {
+  padding: 0.75rem 1rem;
+  border-bottom: 1px solid var(--border);
+  background: var(--bg);
+}
+
+.file-breadcrumbs {
+  font-size: 0.875rem;
+  font-family: monospace;
+}
+
+.breadcrumb-sep {
+  color: var(--muted);
+  margin: 0 0.25rem;
+}
+
+.file-content {
+  padding: 1rem;
+  overflow: auto;
+  max-height: calc(100vh - 200px);
+}
+
+.file-content pre {
+  margin: 0;
+  font-family: "IBM Plex Mono", monospace;
+  font-size: 0.875rem;
+  line-height: 1.5;
+  white-space: pre-wrap;
+  word-wrap: break-word;
+}
+
+.file-viewer-empty {
+  display: flex;
+  align-items: center;
+  justify-content: center;
+  height: 100%;
+  min-height: 300px;
+}

openspec/changes/archive/2026-05-19-git-history-visualization/.openspec.yaml

@@ -0,0 +1,2 @@
+schema: spec-driven
+created: 2026-05-19

openspec/changes/archive/2026-05-19-git-history-visualization/design.md

@@ -0,0 +1,158 @@
+# Git History Visualization - Design
+
+## Architecture
+
+```
+User → Frontend → Backend API → Git CLI → Repository
+                    ↓
+              Commit Data
+                    ↓
+              Frontend Rendering
+```
+
+## Backend Design
+
+### Git History Extraction
+
+Use `git log --graph` with custom format to get structured data:
+
+```bash
+git log --all --graph --format="%H|%P|%an|%ae|%at|%s" --date=short
+```
+
+This gives us:
+- Commit hash
+- Parent hashes
+- Author name
+- Author email
+- Author timestamp
+- Subject line
+
+### API Endpoints
+
+#### GET /projects/{project_id}/repositories/{repo_id}/history
+
+**Query Parameters:**
+- `view`: "graph" or "list" (default: "graph")
+- `branch`: specific branch to filter (optional)
+- `limit`: max commits to return (default: 100)
+
+**Response (Graph View):**
+```json
+{
+  "commits": [
+    {
+      "hash": "abc123...",
+      "short_hash": "abc123",
+      "parents": ["def456...", "ghi789..."],
+      "author": "John Doe",
+      "email": "john@example.com",
+      "date": "2026-05-19",
+      "timestamp": 1716123456,
+      "message": "feat: add new feature",
+      "branches": ["main", "feature-branch"],
+      "tags": ["v1.0.0"]
+    }
+  ],
+  "branches": ["main", "develop", "feature-branch"],
+  "graph_data": {
+    "columns": 3,
+    "rows": [
+      {
+        "commit_hash": "abc123...",
+        "column": 0,
+        "connections": [
+          {"from_column": 0, "to_column": 1, "type": "merge"}
+        ]
+      }
+    ]
+  }
+}
+```
+
+#### GET /projects/{project_id}/repositories/{repo_id}/commits/{commit_hash}
+
+**Response:**
+```json
+{
+  "hash": "abc123...",
+  "short_hash": "abc123",
+  "parents": ["def456..."],
+  "author": "John Doe",
+  "email": "john@example.com",
+  "date": "2026-05-19",
+  "timestamp": 1716123456,
+  "message": "feat: add new feature\n\nDetailed description here",
+  "stats": {
+    "files_changed": 3,
+    "insertions": 45,
+    "deletions": 12
+  },
+  "diff": "diff --git a/file.txt b/file.txt\n..."
+}
+```
+
+## Frontend Design
+
+### Page Layout
+
+```
+┌─────────────────────────────────────────────────────────┐
+│  Repository Name > History                    [Graph] [List] │
+├─────────────────────────────────────────────────────────┤
+│  ┌──────────────────┐  ┌──────────────────────────────┐  │
+│  │                  │  │                              │  │
+│  │   Graph/List     │  │   Commit Details            │  │
+│  │   View           │  │   (message, author,        │  │
+│  │                  │  │    diff)                     │  │
+│  │                  │  │                              │  │
+│  └──────────────────┘  └──────────────────────────────┘  │
+└─────────────────────────────────────────────────────────┘
+```
+
+### Graph View
+
+- SVG-based rendering
+- Commits shown as circles
+- Lines connect commits (straight or curved)
+- Branch labels shown inline
+- Color coding for different branches
+- Click to select commit
+
+### List View
+
+- Linear list of commits
+- Each row: hash, message, author, date
+- Expandable for details
+- Click to select commit
+
+### Commit Details Panel
+
+- Header: Commit message, author, date
+- Stats: Files changed, insertions, deletions
+- Diff view: Syntax highlighted changes
+
+## Data Flow
+
+1. User navigates to repository history page
+2. Frontend fetches history data from backend
+3. Backend executes git commands on bare repo
+4. Backend parses output into structured JSON
+5. Frontend renders graph or list based on user preference
+6. User clicks commit → Frontend fetches commit details
+7. Backend executes `git show` for specific commit
+8. Frontend displays details panel with diff
+
+## Error Handling
+
+- **Empty repository**: Show "No commits yet" message
+- **Git command failure**: Show error with retry button
+- **Large repositories**: Implement pagination/lazy loading
+- **Binary files in diff**: Show "Binary file changed" instead of diff
+
+## Performance Considerations
+
+- **Pagination**: Load commits in batches (100 at a time)
+- **Lazy loading**: Load diff only when commit is selected
+- **Caching**: Cache history data for 30 seconds
+- **Graph complexity**: Limit graph to first 500 commits for performance

openspec/changes/archive/2026-05-19-git-history-visualization/proposal.md

@@ -0,0 +1,46 @@
+# Git History Visualization
+
+## Problem
+
+Currently, users can create and manage git repositories, but they have no way to view the commit history, branches, or understand the repository structure. This makes it impossible to:
+- See what commits exist in a repository
+- Understand branch relationships and merges
+- View commit details (message, author, date, changes)
+- Explore the repository's evolution over time
+
+## Solution
+
+Build an interactive git history visualization similar to GitKraken that provides:
+1. **Graph View**: Visual commit graph showing branches, merges, and commit relationships
+2. **List View**: Linear commit log with details
+3. **Commit Details**: Click any commit to see full details and diff
+4. **Branch Visualization**: See all branches and their relationships
+
+## Benefits
+
+- **Understand repository structure** at a glance
+- **Track changes** and see who made what changes when
+- **Navigate history** easily without using command line
+- **Review code** by examining commit diffs
+
+## Scope
+
+### What we're building:
+- Backend API to extract git history from bare/mirror repos using git CLI
+- Graph visualization component (SVG-based commit graph)
+- List view component (linear commit log)
+- Commit detail panel (message, author, date, diff)
+- View toggle (graph vs list)
+- Branch label display
+
+### Out of scope (future enhancements):
+- Interactive branch operations (checkout, merge, rebase)
+- Tag management
+- File browser at specific commits
+- Blame/annotation view
+- Advanced filtering/search
+
+## Technical Approach
+
+**Backend**: Execute `git log --graph --format=...` commands to get structured commit data
+**Frontend**: Custom SVG rendering for graph, React components for list view and details panel

openspec/changes/archive/2026-05-19-git-history-visualization/specs/spec.md

@@ -0,0 +1,213 @@
+# Git History Visualization Specification
+
+## Requirements
+
+### Functional Requirements
+
+1. **View Commit History**: Display all commits in a repository
+2. **Graph Visualization**: Show commits as nodes with branch/merge lines
+3. **List View**: Alternative linear view of commits
+4. **Commit Details**: Click to view full commit info and diff
+5. **Branch Display**: Show branch names on commits
+6. **Tag Display**: Show tags on commits
+7. **View Toggle**: Switch between graph and list views
+
+### Non-Functional Requirements
+
+1. **Performance**: Load first 100 commits in < 2 seconds
+2. **Responsiveness**: Graph should render smoothly up to 500 commits
+3. **Compatibility**: Work with bare repositories and mirror clones
+4. **Read-only**: No write operations to repository
+
+## API Specification
+
+### GET /projects/{project_id}/repositories/{repo_id}/history
+
+Retrieve commit history for a repository.
+
+**Query Parameters:**
+| Parameter | Type | Default | Description |
+|-----------|------|---------|-------------|
+| view | string | "graph" | "graph" or "list" |
+| branch | string | null | Filter by branch name |
+| limit | integer | 100 | Max commits to return |
+| offset | integer | 0 | Skip first N commits |
+
+**Response 200:**
+```json
+{
+  "commits": [
+    {
+      "hash": "full-sha-hash",
+      "short_hash": "abc1234",
+      "parents": ["parent-hash-1", "parent-hash-2"],
+      "author": "John Doe",
+      "email": "john@example.com",
+      "date": "2026-05-19",
+      "timestamp": 1716123456,
+      "message": "feat: add new feature",
+      "branches": ["main"],
+      "tags": []
+    }
+  ],
+  "branches": ["main", "develop", "feature/x"],
+  "total_commits": 250,
+  "graph_data": {
+    "nodes": [
+      {
+        "hash": "abc1234",
+        "x": 0,
+        "y": 0,
+        "column": 0
+      }
+    ],
+    "edges": [
+      {
+        "from_hash": "abc1234",
+        "to_hash": "def5678",
+        "type": "parent"
+      }
+    ]
+  }
+}
+```
+
+### GET /projects/{project_id}/repositories/{repo_id}/commits/{commit_hash}
+
+Get detailed information about a specific commit.
+
+**Response 200:**
+```json
+{
+  "hash": "full-sha-hash",
+  "short_hash": "abc1234",
+  "parents": ["parent-hash"],
+  "author": "John Doe",
+  "email": "john@example.com",
+  "date": "2026-05-19",
+  "timestamp": 1716123456,
+  "message": "feat: add new feature",
+  "body": "Detailed description here",
+  "stats": {
+    "files_changed": 3,
+    "insertions": 45,
+    "deletions": 12
+  },
+  "files": [
+    {
+      "path": "src/main.py",
+      "change_type": "modified",
+      "insertions": 20,
+      "deletions": 5,
+      "diff": "diff content here"
+    }
+  ]
+}
+```
+
+## Frontend Components
+
+### GitHistoryPage
+Main page component that orchestrates the view.
+
+### GraphView
+SVG-based commit graph visualization.
+
+**Props:**
+- `commits`: Commit[]
+- `graphData`: GraphData
+- `selectedCommit`: string | null
+- `onCommitSelect`: (hash: string) => void
+
+### ListView
+Linear commit list.
+
+**Props:**
+- `commits`: Commit[]
+- `selectedCommit`: string | null
+- `onCommitSelect`: (hash: string) => void
+
+### CommitDetails
+Panel showing commit details and diff.
+
+**Props:**
+- `commit`: CommitDetail | null
+
+### DiffViewer
+Component to display git diff with syntax highlighting.
+
+**Props:**
+- `files`: FileChange[]
+
+## Data Models
+
+### Commit
+```typescript
+interface Commit {
+  hash: string;
+  short_hash: string;
+  parents: string[];
+  author: string;
+  email: string;
+  date: string;
+  timestamp: number;
+  message: string;
+  branches: string[];
+  tags: string[];
+}
+```
+
+### CommitDetail
+```typescript
+interface CommitDetail extends Commit {
+  body: string;
+  stats: {
+    files_changed: number;
+    insertions: number;
+    deletions: number;
+  };
+  files: FileChange[];
+}
+```
+
+### FileChange
+```typescript
+interface FileChange {
+  path: string;
+  change_type: "added" | "modified" | "deleted" | "renamed";
+  insertions: number;
+  deletions: number;
+  diff: string;
+}
+```
+
+## URL Structure
+
+```
+/projects/:projectId/repositories/:repoId/history
+```
+
+## Error Codes
+
+| Error Code | Description | User Message |
+|------------|-------------|--------------|
+| REPO_EMPTY | Repository has no commits | "This repository has no commits yet" |
+| GIT_ERROR | Git command failed | "Failed to load repository history" |
+| COMMIT_NOT_FOUND | Commit hash not found | "Commit not found" |
+| INVALID_BRANCH | Branch doesn't exist | "Branch not found" |
+
+## Testing Strategy
+
+### Backend Tests
+- Test git log parsing with various repo structures
+- Test commit detail extraction
+- Test error handling for empty repos
+
+### Frontend Tests
+- Test graph rendering with sample data
+- Test list view rendering
+- Test commit selection and details display
+- Test view toggle
+
+### Integration Tests
+- End-to-end flow: load history → select commit → view details

openspec/changes/archive/2026-05-19-git-history-visualization/tasks.md

@@ -0,0 +1,113 @@
+# Git History Visualization - Tasks
+
+## Phase 1: Backend API
+
+- [x] **Task 1.1**: Create git history extraction module
+  - Create `src/utils/git_history.py`
+  - Implement `get_commit_history(repo_path, limit=100)` function
+  - Parse `git log --graph --format=...` output
+  - Extract commit hashes, parents, authors, dates, messages
+  - Extract branch information
+  - Add comprehensive unit tests
+
+- [x] **Task 1.2**: Create commit detail extraction
+  - Implement `get_commit_detail(repo_path, commit_hash)` function
+  - Parse `git show --format=... --stat` output
+  - Extract full message, body, stats, file changes
+  - Extract diff for each file
+  - Add unit tests
+
+- [x] **Task 1.3**: Create graph data builder
+  - Implement `build_graph_data(commits)` function
+  - Calculate node positions (x, y coordinates)
+  - Calculate edge connections between commits
+  - Handle merge commits (multiple parents)
+  - Add unit tests
+
+- [x] **Task 1.4**: Create history API endpoints
+  - Add `GET /projects/{project_id}/repositories/{repo_id}/history`
+  - Add `GET /projects/{project_id}/repositories/{repo_id}/commits/{commit_hash}`
+  - Handle query parameters (view, branch, limit, offset)
+  - Return structured JSON response
+  - Handle errors (empty repo, invalid commit, etc.)
+  - Add integration tests
+
+## Phase 2: Frontend Components
+
+- [x] **Task 2.1**: Create API client for history
+  - Add `fetchHistory(projectId, repoId, options)` function
+  - Add `fetchCommitDetail(projectId, repoId, commitHash)` function
+  - Add TypeScript interfaces for all data types
+
+- [x] **Task 2.2**: Create GraphView component
+  - SVG-based commit graph rendering
+  - Draw commit nodes (circles)
+  - Draw connection lines (straight/curved)
+  - Show branch labels
+  - Handle click events
+  - Color coding for branches
+
+- [x] **Task 2.3**: Create ListView component
+  - Linear list of commits
+  - Show hash, message, author, date
+  - Handle click events
+  - Scrollable with virtualization for large lists
+
+- [x] **Task 2.4**: Create CommitDetails component
+  - Show commit message, author, date
+  - Show stats (files changed, insertions, deletions)
+  - Show file list with change types
+  - Expandable diff viewer
+  - Syntax highlighting for diffs
+
+- [x] **Task 2.5**: Create DiffViewer component
+  - Parse and display git diff format
+  - Show line numbers
+  - Color code: green for additions, red for deletions
+  - Handle binary files
+  - Collapsible file sections
+
+## Phase 3: Page Integration
+
+- [x] **Task 3.1**: Create GitHistoryPage
+  - Layout with view toggle (graph/list)
+  - Fetch history data on mount
+  - Manage selected commit state
+  - Show loading/error states
+  - Responsive layout (details panel on right, below on mobile)
+
+- [x] **Task 3.2**: Add navigation from repository list
+  - Add "View History" button to repository cards
+  - Link to history page
+  - Pass repository info
+
+- [x] **Task 3.3**: Add route
+  - Add `/projects/:projectId/repositories/:repoId/history` route
+  - Update router configuration
+
+## Phase 4: Testing & Polish
+
+- [ ] **Task 4.1**: Add backend tests
+  - Test git log parsing
+  - Test graph data building
+  - Test API endpoints
+  - Test error handling
+
+- [ ] **Task 4.2**: Add frontend tests
+  - Test component rendering
+  - Test user interactions (click, toggle)
+  - Test data transformations
+
+- [x] **Task 4.3**: Run quality gates
+  - Backend: ruff, mypy, pytest
+  - Frontend: typecheck, lint, build
+
+- [ ] **Task 4.4**: Performance optimization
+  - Implement pagination for large repositories
+  - Add caching for history data
+  - Optimize graph rendering
+
+- [ ] **Task 4.5**: Documentation
+  - Update README with feature description
+  - Add screenshots/diagrams
+  - Document API endpoints

openspec/changes/repo-workspace/.openspec.yaml

@@ -0,0 +1,2 @@
+schema: spec-driven
+created: 2026-05-19

openspec/changes/repo-workspace/design.md

@@ -0,0 +1,269 @@
+# Repository Workspace - Design
+
+## Architecture
+
+```
+Project List
+    ↓ (click project)
+Repo Workspace (default view)
+    ├─ Sidebar (200px)
+    │   ├─ Repo Selector (dropdown)
+    │   ├─ Branch Selector (dropdown)
+    │   └─ File Tree (scrollable)
+    │       ├─ 📁 src/
+    │       │   └─ 📄 main.py
+    │       ├─ 📁 tests/
+    │       └─ 📄 README.md
+    │
+    └─ Main Content
+        ├─ Breadcrumbs: src > main.py
+        ├─ Toolbar: [Edit] [Raw] [History]
+        └─ Content Area
+            ├─ File View (syntax highlighted)
+            └─ Edit View (textarea with save)
+```
+
+## Page Layout
+
+### Route: `/projects/:projectId`
+This replaces the current placeholder and becomes the default project view.
+
+### Layout Structure
+```
+┌─────────────────────────────────────────────────────────────┐
+│  App Shell (Header + Nav)                                    │
+├─────────────────────────────────────────────────────────────┤
+│  Project Header                                              │
+│  "My Project"                    [Repos] [History] [Settings]│
+├─────────────────┬───────────────────────────────────────────┤
+│                 │                                           │
+│  Sidebar        │  Main Content                             │
+│  ┌───────────┐  │  ┌─────────────────────────────────────┐  │
+│  │ Repo ▼    │  │  │ Breadcrumbs: src > components       │  │
+│  ├───────────┤  │  ├─────────────────────────────────────┤  │
+│  │ Branch ▼  │  │  │ [Edit] [History] [Blame]            │  │
+│  ├───────────┤  │  ├─────────────────────────────────────┤  │
+│  │ 📁 src/   │  │  │                                     │  │
+│  │ 📁 tests/ │  │  │ function hello() {                  │  │
+│  │ 📄 README │  │  │   return "world";                   │  │
+│  │ ...       │  │  │ }                                   │  │
+│  │           │  │  │                                     │  │
+│  └───────────┘  │  └─────────────────────────────────────┘  │
+│                 │                                           │
+└─────────────────┴───────────────────────────────────────────┘
+```
+
+## Data Flow
+
+### 1. Page Load
+```
+Load /projects/:id
+→ Fetch project details
+→ Fetch repositories list
+→ Fetch default branch file tree (first repo)
+→ Render workspace
+```
+
+### 2. Repository Switch
+```
+Select repo from dropdown
+→ Fetch branches list
+→ Fetch default branch file tree
+→ Reset file viewer
+```
+
+### 3. Branch Switch
+```
+Select branch from dropdown
+→ Fetch file tree for branch
+→ If viewing a file: re-fetch file content for branch
+```
+
+### 4. File Navigation
+```
+Click file in tree
+→ Fetch file content (with syntax highlighting hint)
+→ Show in viewer
+→ Update breadcrumbs
+```
+
+## API Endpoints
+
+### GET /projects/{project_id}/repositories/{repo_id}/files
+List files at a path (like `ls` for git).
+
+**Query Parameters:**
+- `branch`: Branch name (default: repo's default branch)
+- `path`: Directory path (default: root)
+
+**Response:**
+```json
+{
+  "path": "src",
+  "branch": "main",
+  "entries": [
+    {
+      "name": "components",
+      "type": "directory",
+      "path": "src/components"
+    },
+    {
+      "name": "main.py",
+      "type": "file",
+      "path": "src/main.py",
+      "size": 1234,
+      "last_commit": {
+        "hash": "abc123",
+        "message": "Initial commit",
+        "date": "2024-01-01T00:00:00Z"
+      }
+    }
+  ]
+}
+```
+
+### GET /projects/{project_id}/repositories/{repo_id}/files/content
+Get file content.
+
+**Query Parameters:**
+- `branch`: Branch name
+- `path`: File path
+
+**Response:**
+```json
+{
+  "path": "src/main.py",
+  "branch": "main",
+  "content": "function hello() {\n  return 'world';\n}",
+  "size": 42,
+  "encoding": "utf-8",
+  "language": "python"
+}
+```
+
+### GET /projects/{project_id}/repositories/{repo_id}/branches
+List branches.
+
+**Response:**
+```json
+{
+  "branches": [
+    {
+      "name": "main",
+      "is_default": true,
+      "last_commit": "abc123"
+    },
+    {
+      "name": "feature/new-thing",
+      "is_default": false,
+      "last_commit": "def456"
+    }
+  ],
+  "default_branch": "main"
+}
+```
+
+### POST /projects/{project_id}/repositories/{repo_id}/files/content
+Update file content (for quick edits).
+
+**Request Body:**
+```json
+{
+  "path": "src/main.py",
+  "branch": "main",
+  "content": "function hello() {\n  return 'world!!!';\n}",
+  "commit_message": "Quick edit: update greeting",
+  "author_name": "User Name",
+  "author_email": "user@example.com"
+}
+```
+
+## Components
+
+### RepoWorkspace (Page)
+- Orchestrates layout: sidebar + main content
+- Manages repo/branch/file state
+- Handles URL params (projectId, optional repoId)
+
+### FileTree (Sidebar Component)
+- Recursive tree view
+- Expandable folders
+- File icons based on extension
+- Active file highlight
+- Click to open file
+
+### RepoSelector (Component)
+- Dropdown of project repositories
+- Shows active repo name
+- Switch triggers repo change
+
+### BranchSelector (Component)
+- Dropdown of branches
+- Shows active branch
+- Switch triggers branch change
+
+### FileViewer (Component)
+- Syntax highlighted content
+- Line numbers
+- View/Edit toggle
+- Breadcrumb navigation
+
+### Breadcrumbs (Component)
+- Path segments as clickable links
+- Shows current file location
+
+## State Management
+
+### URL State
+```
+/projects/:projectId?repo=:repoId&branch=:branch&path=:path
+```
+- repo: selected repository ID
+- branch: active branch name
+- path: current file/directory path
+
+### React State (per workspace)
+```typescript
+interface WorkspaceState {
+  projectId: string;
+  selectedRepoId: string | null;
+  selectedBranch: string;
+  currentPath: string;
+  selectedFile: string | null;
+  fileContent: string | null;
+  isEditing: boolean;
+  fileTree: FileTreeEntry[];
+  branches: Branch[];
+  repositories: Repository[];
+}
+```
+
+## Implementation Order
+
+1. **Backend file APIs** - List files, get content, list branches
+2. **Backend update API** - Save file changes (commit)
+3. **Project list clickable** - Link to workspace
+4. **Workspace page shell** - Layout with sidebar + main
+5. **File tree component** - Recursive directory listing
+6. **File viewer component** - Content display
+7. **Repo/branch selectors** - Dropdowns with state
+8. **Edit mode** - Toggle + save
+9. **URL state sync** - Sync selections to URL
+10. **Polish** - Icons, syntax highlighting, error handling
+
+## Error Handling
+
+- **Repo not found**: Show error, allow selecting another
+- **Branch not found**: Show error, default to main
+- **File not found**: Show 404 in viewer
+- **Permission denied**: Show auth error
+- **Binary files**: Show "Binary file, cannot display" message
+- **Large files**: Show warning, offer download
+
+## Performance Considerations
+
+- **Lazy load file tree**: Only expand directories when clicked
+- **Cache file content**: Don't re-fetch if file hasn't changed
+- **Debounce tree loading**: When switching branches, debounce
+- **Virtual scrolling**: For large directories (100+ files)
+- **Syntax highlighting**: Use lightweight highlighter, async load

openspec/changes/repo-workspace/proposal.md

@@ -0,0 +1,72 @@
+# Repository Workspace - Default Project View
+
+## Problem
+
+Currently, clicking on a project shows a generic placeholder. Users need to navigate to repositories separately. There's no easy way to browse repository files or see project content at a glance.
+
+## Solution
+
+Create a **Repository Workspace** as the default project view that provides:
+
+1. **File browser** for repositories - browse files and directories
+2. **Branch selector** - switch between branches
+3. **Mini file viewer** - view file contents with syntax highlighting
+4. **Quick edit capability** - small edits without leaving the browser
+5. **Repository overview** - see all repos in the project
+
+This becomes the default view when clicking on a project, making the project the central workspace.
+
+## Key Features
+
+### Default Project View
+- Clicking any project opens the repository workspace
+- Shows first repo by default (or repo selector if multiple)
+- File browser on the left, content viewer on the right
+
+### File Browser
+- Tree view of repository files and directories
+- Expandable/collapsible folders
+- Click file to view contents
+- Breadcrumb navigation
+
+### Branch Management
+- Branch selector dropdown
+- Shows current branch
+- Lists all branches (local + remote)
+- Switch branches to view different states
+
+### File Viewer
+- Syntax highlighting for common file types
+- Line numbers
+- View mode (read-only by default)
+- Edit mode toggle for small changes
+
+### Repository Navigation
+- List all repositories in the project
+- Quick switch between repos
+- Repository cards with metadata (last commit, branch count)
+
+## Benefits
+
+- **Central hub**: Project becomes the main workspace, not just a container
+- **Quick access**: See code immediately without extra clicks
+- **Contextual**: Browse files while viewing commit history
+- **Familiar**: Similar to GitHub/GitLab file browser
+
+## Scope
+
+### What stays:
+- Existing repository list page (moves to sub-page)
+- Git history visualization
+- Repository creation/deletion
+
+### What's new:
+- Repository workspace page (default project view)
+- File browser component
+- File viewer component
+- Branch selector component
+- API endpoints for file operations
+
+### What's changed:
+- Project list items become clickable links
+- Default project route shows workspace instead of placeholder

openspec/changes/repo-workspace/specs/spec.md

@@ -0,0 +1,257 @@
+# Repository Workspace Specification
+
+## Requirements
+
+### Functional Requirements
+
+1. **Default Project View**: Clicking a project opens the repository workspace
+2. **File Browser**: Tree view of repository files and directories
+3. **Branch Navigation**: Switch between branches to view different states
+4. **File Viewer**: View file contents with syntax highlighting
+5. **Quick Edit**: Make small changes and commit them
+6. **Repository Switching**: Switch between repositories in a project
+7. **Breadcrumb Navigation**: Show current file path with clickable segments
+
+### Non-Functional Requirements
+
+1. **Performance**: File tree loads in < 1 second
+2. **Responsiveness**: UI remains responsive during git operations
+3. **Usability**: Familiar interface similar to GitHub/GitLab
+4. **Accessibility**: Keyboard navigation, screen reader support
+
+## API Specification
+
+### GET /projects/{project_id}/repositories/{repo_id}/files
+List files in a directory.
+
+**Query Parameters:**
+- `branch` (optional): Branch name, defaults to repository default branch
+- `path` (optional): Directory path, defaults to root
+
+**Response 200:**
+```json
+{
+  "path": "src",
+  "branch": "main",
+  "entries": [
+    {
+      "name": "components",
+      "type": "directory",
+      "path": "src/components",
+      "mode": "040000"
+    },
+    {
+      "name": "main.py",
+      "type": "file",
+      "path": "src/main.py",
+      "size": 1234,
+      "mode": "100644",
+      "last_commit": {
+        "hash": "abc123",
+        "message": "Initial commit",
+        "author": "John Doe",
+        "date": "2024-01-01T00:00:00Z"
+      }
+    }
+  ]
+}
+```
+
+**Response 404:** Branch or path not found
+
+### GET /projects/{project_id}/repositories/{repo_id}/files/content
+Get file content.
+
+**Query Parameters:**
+- `branch` (required): Branch name
+- `path` (required): File path
+
+**Response 200:**
+```json
+{
+  "path": "src/main.py",
+  "branch": "main",
+  "content": "function hello() {\n  return 'world';\n}",
+  "size": 42,
+  "encoding": "utf-8",
+  "language": "python",
+  "is_binary": false,
+  "last_commit": {
+    "hash": "abc123",
+    "message": "Initial commit",
+    "author": "John Doe",
+    "date": "2024-01-01T00:00:00Z"
+  }
+}
+```
+
+**Response 404:** File not found
+
+### GET /projects/{project_id}/repositories/{repo_id}/branches
+List branches.
+
+**Response 200:**
+```json
+{
+  "branches": [
+    {
+      "name": "main",
+      "is_default": true,
+      "last_commit": {
+        "hash": "abc123",
+        "message": "Initial commit",
+        "date": "2024-01-01T00:00:00Z"
+      }
+    }
+  ],
+  "default_branch": "main"
+}
+```
+
+### POST /projects/{project_id}/repositories/{repo_id}/files/content
+Update file content.
+
+**Request Body:**
+```json
+{
+  "path": "src/main.py",
+  "branch": "main",
+  "content": "new content",
+  "commit_message": "Update file",
+  "author_name": "User",
+  "author_email": "user@example.com"
+}
+```
+
+**Response 200:**
+```json
+{
+  "commit_hash": "def789",
+  "message": "Update file",
+  "branch": "main"
+}
+```
+
+## Data Model
+
+### FileTreeEntry
+```typescript
+interface FileTreeEntry {
+  name: string;
+  type: 'file' | 'directory';
+  path: string;
+  size?: number;
+  mode?: string;
+  last_commit?: {
+    hash: string;
+    message: string;
+    author: string;
+    date: string;
+  };
+}
+```
+
+### Branch
+```typescript
+interface Branch {
+  name: string;
+  is_default: boolean;
+  last_commit?: {
+    hash: string;
+    message: string;
+    date: string;
+  };
+}
+```
+
+### FileContent
+```typescript
+interface FileContent {
+  path: string;
+  branch: string;
+  content: string;
+  size: number;
+  encoding: string;
+  language: string | null;
+  is_binary: boolean;
+  last_commit?: {
+    hash: string;
+    message: string;
+    author: string;
+    date: string;
+  };
+}
+```
+
+## Frontend Specification
+
+### URL Structure
+```
+/projects/:projectId                    → Default view (first repo, default branch)
+/projects/:projectId?repo=:repoId       → Specific repo
+/projects/:projectId?repo=:repoId&branch=:branch&path=:path  → Specific file
+```
+
+### Components
+
+**RepoWorkspace**
+- Layout: Sidebar (250px) + Main Content (flex)
+- State: manages repo, branch, path, file selections
+- Effects: sync URL params, fetch data
+
+**FileTree**
+- Props: entries, activePath, onFileClick, onDirectoryToggle
+- Recursive rendering for nested directories
+- Expand/collapse state per directory
+
+**FileViewer**
+- Props: content, language, path, isEditing, onEdit
+- View mode: preformatted text with syntax highlighting
+- Edit mode: textarea with save/cancel
+
+**RepoSelector**
+- Props: repositories, selectedRepoId, onSelect
+- Dropdown with repo names
+
+**BranchSelector**
+- Props: branches, selectedBranch, onSelect
+- Dropdown with branch names, default branch marked
+
+### State Management
+Use React state with URL synchronization:
+```typescript
+const [searchParams, setSearchParams] = useSearchParams();
+const repoId = searchParams.get('repo');
+const branch = searchParams.get('branch');
+const path = searchParams.get('path');
+```
+
+## Error Codes
+
+| Error Code | Description | User Message |
+|------------|-------------|--------------|
+| REPO_NOT_FOUND | Repository doesn't exist | "Repository not found" |
+| BRANCH_NOT_FOUND | Branch doesn't exist | "Branch not found, using default" |
+| FILE_NOT_FOUND | File path doesn't exist | "File not found" |
+| BINARY_FILE | File is binary | "Cannot display binary file" |
+| PERMISSION_DENIED | No access to file | "Permission denied" |
+
+## Testing Strategy
+
+### Backend Tests
+- Test file listing for various paths
+- Test file content retrieval
+- Test branch listing
+- Test file update/commit
+- Test error cases (missing files, invalid branches)
+
+### Frontend Tests
+- Test file tree rendering
+- Test file viewer display
+- Test branch switching
+- Test repo switching
+- Test edit mode
+- Test URL state sync
+
+### Integration Tests
+- End-to-end: Click project → browse files → view content → switch branch

openspec/changes/repo-workspace/tasks.md

@@ -0,0 +1,131 @@
+# Repository Workspace - Tasks
+
+## Phase 1: Backend File APIs
+
+- [ ] **Task 1.1**: Create git file utilities
+  - Create `src/utils/git_files.py`
+  - `list_tree()` - list files in directory using `git ls-tree`
+  - `get_file_content()` - get file content using `git show`
+  - `list_branches()` - list branches using `git branch`
+  - `commit_file()` - commit file changes using `git add` + `git commit`
+  - Add tests
+
+- [ ] **Task 1.2**: Add file listing endpoint
+  - Add `GET /projects/{id}/repositories/{id}/files` to git_repositories.py
+  - Query params: branch, path
+  - Returns FileTreeEntry list
+  - Handle errors (missing branch, missing path)
+
+- [ ] **Task 1.3**: Add file content endpoint
+  - Add `GET /projects/{id}/repositories/{id}/files/content` to git_repositories.py
+  - Query params: branch, path
+  - Returns FileContent with language detection
+  - Detect binary files
+
+- [ ] **Task 1.4**: Add branches endpoint
+  - Add `GET /projects/{id}/repositories/{id}/branches` to git_repositories.py
+  - Returns branch list with default branch marked
+
+- [ ] **Task 1.5**: Add file update endpoint
+  - Add `POST /projects/{id}/repositories/{id}/files/content` to git_repositories.py
+  - Body: path, branch, content, commit_message, author info
+  - Create commit with changes
+  - Return commit hash
+
+## Phase 2: Project List Navigation
+
+- [ ] **Task 2.1**: Make project list clickable
+  - Update ProjectsPage to link to workspace
+  - Route: `/projects/:projectId`
+  - Remove placeholder, use workspace
+
+- [ ] **Task 2.2**: Update app navigation
+  - Ensure project routes are correct
+  - Add breadcrumb or back button
+
+## Phase 3: Workspace Page Shell
+
+- [ ] **Task 3.1**: Create RepoWorkspace page
+  - Create `pages/repo-workspace.tsx`
+  - Layout: Sidebar + Main Content
+  - Fetch project repos on load
+  - Select first repo by default
+
+- [ ] **Task 3.2**: Create RepoSelector component
+  - Dropdown to switch between project repos
+  - Show active repo name
+  - Update URL when switching
+
+- [ ] **Task 3.3**: Create BranchSelector component
+  - Dropdown to switch branches
+  - Show active branch
+  - Mark default branch
+  - Fetch branches from API
+
+## Phase 4: File Browser
+
+- [ ] **Task 4.1**: Create FileTree component
+  - Recursive tree view
+  - Expandable/collapsible folders
+  - File icons by extension
+  - Click to open file
+  - Active file highlight
+  - Fetch tree data from API
+
+- [ ] **Task 4.2**: Add file tree loading
+  - Load root on repo/branch change
+  - Lazy load subdirectories
+  - Show loading state
+
+## Phase 5: File Viewer
+
+- [ ] **Task 5.1**: Create FileViewer component
+  - Display file content
+  - Line numbers
+  - Syntax highlighting (prismjs or similar)
+  - Breadcrumb navigation
+  - Show file metadata (size, last commit)
+
+- [ ] **Task 5.2**: Add edit mode
+  - Toggle between view/edit
+  - Textarea for editing
+  - Save button (calls update API)
+  - Cancel button
+  - Commit message input
+
+## Phase 6: Integration & Polish
+
+- [ ] **Task 6.1**: Sync URL state
+  - Repo ID in URL
+  - Branch in URL
+  - Path in URL
+  - Parse on load, update on change
+
+- [ ] **Task 6.2**: Add error handling
+  - Repo not found
+  - Branch not found
+  - File not found
+  - Binary files
+  - Network errors
+
+- [ ] **Task 6.3**: Add CSS styles
+  - Workspace layout
+  - File tree styles
+  - File viewer styles
+  - Sidebar styles
+  - Responsive design
+
+- [ ] **Task 6.4**: Run quality gates
+  - Backend: ruff, mypy, pytest
+  - Frontend: typecheck, lint, build
+
+## Phase 7: Route Updates
+
+- [ ] **Task 7.1**: Update router
+  - `/projects/:projectId` → RepoWorkspace (default)
+  - Move old project details to `/projects/:projectId/details` or remove
+  - Keep `/projects/:projectId/repositories` for repo management
+
+- [ ] **Task 7.2**: Update navigation
+  - Project list links to workspace
+  - Add "Manage Repositories" link in workspace