feat: implement git repository management

- Add backend API for git repository CRUD (create, list, delete)
- Support bare repository initialization and mirror cloning
- Add cascade delete for repositories when project is deleted
- Add frontend page for repository management per project
- Update project page with link to repositories
- Add repo_base_path to config
- Quality gates: ruff, mypy, typecheck, lint, build all pass

apps/web/src/api/git_repositories.ts

@@ -0,0 +1,35 @@
+import { apiClient } from "./client";
+
+export interface GitRepository {
+  id: string;
+  name: string;
+  path: string;
+  project_id: string;
+  owner_id: string;
+  is_mirror: boolean;
+  remote_url: string | null;
+  last_push: string | null;
+  created_at: string | null;
+}
+
+export interface GitRepositoryCreate {
+  name: string;
+  remote_url?: string;
+}
+
+export async function listRepositories(projectId: string): Promise<GitRepository[]> {
+  const response = await apiClient.get(`/projects/${projectId}/repositories`);
+  return response.data;
+}
+
+export async function createRepository(
+  projectId: string,
+  data: GitRepositoryCreate
+): Promise<GitRepository> {
+  const response = await apiClient.post(`/projects/${projectId}/repositories`, data);
+  return response.data;
+}
+
+export async function deleteRepository(projectId: string, repoId: string): Promise<void> {
+  await apiClient.delete(`/projects/${projectId}/repositories/${repoId}`);
+}