refactor: extract global styles and tokens (Task 2.1)

- Create styles/tokens.css with CSS custom properties and dark theme
- Create styles/global.css with resets, shell layout, and navigation
- Create styles/utilities.css with generic utilities and primitives
- Create styles/syntax-highlight.css with Prism.js theme
- Update main.tsx to import the 4 new style files
- Keep styles.css intact for backward compatibility

Quality gates: build (pass), lint (pass)
Refs: repo-restructure Task 2.1

apps/api/src/schemas/config_folder.py

@@ -0,0 +1,42 @@
+"""Config folder request/response schemas."""
+
+from pydantic import BaseModel, Field
+
+
+class ConfigFolderCreate(BaseModel):
+    name: str = Field(description="Folder name")
+    description: str | None = Field(default=None, description="Optional description")
+    mount_path: str = Field(description="Mount path in container")
+    files: dict[str, str] | None = Field(
+        default=None, description="Files as {path: content}"
+    )
+    is_active: bool = Field(default=True, description="Whether folder is active")
+
+
+class ConfigFolderUpdate(BaseModel):
+    name: str | None = None
+    description: str | None = None
+    mount_path: str | None = None
+    files: dict[str, str] | None = None
+    is_active: bool | None = None
+
+
+class ProjectOverrideCreate(BaseModel):
+    project_id: str = Field(description="Project ID to override for")
+    mount_path: str | None = Field(default=None, description="Override mount path")
+    files: dict[str, str] | None = Field(
+        default=None, description="Override files"
+    )
+    is_active: bool | None = Field(default=None, description="Override active state")
+
+
+class ConfigFolderResponse(BaseModel):
+    id: str
+    user_id: str
+    name: str
+    description: str | None
+    mount_path: str
+    files: dict[str, str] | None
+    is_active: bool
+    created_at: str
+    updated_at: str