Initial commit: RehearsalHub POC

Full-stack self-hosted band rehearsal platform:

Backend (FastAPI + SQLAlchemy 2.0 async):
- Auth with JWT (register, login, /me, settings)
- Band management with Nextcloud folder integration
- Song management with audio version tracking
- Nextcloud scan to auto-import audio files
- Band membership with link-based invite system
- Song comments
- Audio analysis worker (BPM, key, loudness, waveform)
- Nextcloud activity watcher for auto-import
- WebSocket support for real-time annotation updates
- Alembic migrations (0001–0003)
- Repository pattern, Ruff + mypy configured

Frontend (React 18 + Vite + TypeScript strict):
- Login/register page with post-login redirect
- Home page with band list and creation form
- Band page with member panel, invite link, song list, NC scan
- Song page with waveform player, annotations, comment thread
- Settings page for per-user Nextcloud credentials
- Invite acceptance page (/invite/:token)
- ESLint v9 flat config + TypeScript strict mode

Infrastructure:
- Docker Compose: PostgreSQL, Redis, API, worker, watcher, nginx
- nginx reverse proxy for static files + /api/ proxy
- make check runs all linters before docker compose build

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

api/src/rehearsalhub/routers/__init__.py

@@ -0,0 +1,19 @@
+from rehearsalhub.routers.annotations import router as annotations_router
+from rehearsalhub.routers.auth import router as auth_router
+from rehearsalhub.routers.bands import router as bands_router
+from rehearsalhub.routers.internal import router as internal_router
+from rehearsalhub.routers.members import router as members_router
+from rehearsalhub.routers.songs import router as songs_router
+from rehearsalhub.routers.versions import router as versions_router
+from rehearsalhub.routers.ws import router as ws_router
+
+__all__ = [
+    "auth_router",
+    "bands_router",
+    "internal_router",
+    "members_router",
+    "songs_router",
+    "versions_router",
+    "annotations_router",
+    "ws_router",
+]