test: add tests for extracted components (Task 5.1)

- LoadingState.test.tsx: default/custom message rendering
- ErrorState.test.tsx: message, retry button, callback
- FileBrowser.test.tsx: loading, entries, error states
- ToolTypesTab.test.tsx: loading, content, error states
- SessionCard.test.tsx: active/recent variants, unnamed fallback
- CreateSessionForm.test.tsx: render, validation, repo loading
- Fix vite.config.ts resolve.alias for @/ path mapping in tests

Quality gates: vitest 17 new tests pass, 70/74 total pass
(pre-existing 4 failures in projects.test.tsx unrelated)
Refs: repo-restructure Task 5.1

openspec/changes/repo-restructure/apply-5.1-report.md

@@ -0,0 +1,34 @@
+# Task 5.1 Apply Report: Add Tests for Extracted Components
+
+**Status:** Success
+
+## Files Created (6)
+
+- `apps/web/src/components/ui/LoadingState.test.tsx` — 2 tests: default message, custom message
+- `apps/web/src/components/ui/ErrorState.test.tsx` — 3 tests: message render, no retry button, retry callback
+- `apps/web/src/components/features/git/FileBrowser.test.tsx` — 3 tests: loading state, file entries after load, error state
+- `apps/web/src/components/features/tool-workshop/ToolTypesTab.test.tsx` — 3 tests: loading state, heading after load, error state
+- `apps/web/src/components/features/session/SessionCard.test.tsx` — 3 tests: active variant, recent variant, unnamed fallback
+- `apps/web/src/components/features/session/CreateSessionForm.test.tsx` — 3 tests: form render, validation error, repository loading
+
+## Files Modified (1)
+
+- `apps/web/vite.config.ts` — Added `resolve.alias` for `@/` path mapping to support test file imports
+
+## Quality Gate Results
+
+| Gate | Result |
+|------|--------|
+| New tests (6 files) | ✅ 17 passed |
+| Full test suite | ✅ 70 passed / 74 total |
+| Pre-existing failures | 4 tests in `projects.test.tsx` (React Router context issue — pre-existing, unrelated) |
+| Typecheck | ✅ PASS |
+| Lint | ✅ PASS |
+
+## Notes
+
+- All tests use Vitest + React Testing Library (jsdom environment)
+- API calls mocked with `vi.mock()` and `vi.fn()`
+- `MemoryRouter` used for components with `useSearchParams`
+- No test file exceeds 200 lines
+- No existing tests were broken by changes