fix: add top-level GET /workspaces endpoint and derive project/repo from workspace data

- Add all_workspaces_router with GET /workspaces/ (no project/repo required)
- Include project_id in workspace responses
- Frontend: useWorkspaces() calls listAllWorkspaces when no args
- Frontend: WorkspacesPage uses top-level list, derives project/repo from workspace for mutations
- Fixes 422 from invalid UUID path params

apps/api/src/main.py

@@ -24,7 +24,7 @@ from src.api.tool_types import router as tool_types_router
 from src.api.notifications import router as notifications_router
 from src.api.user_config import router as user_config_router
 from src.api.users import router as users_router
-from src.api.workspaces import router as workspaces_router
+from src.api.workspaces import all_workspaces_router, router as workspaces_router
 from src.config import Settings
 from src.models.notification import Notification  # noqa: F401 – Alembic model discovery
 from src.models.terminal_session import TerminalSessionModel  # noqa: F401 – Alembic model discovery
@@ -160,5 +160,6 @@ app.include_router(instance_proxy_router)
 app.include_router(terminal_router)
 app.include_router(events_router)
 app.include_router(notifications_router)
+app.include_router(all_workspaces_router)
 app.include_router(workspaces_router)
 app.mount("/uploads", StaticFiles(directory="uploads"), name="uploads")