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/ws.py

@@ -0,0 +1,46 @@
+"""WebSocket connection manager for real-time version room events."""
+
+from __future__ import annotations
+
+import json
+import uuid
+from typing import Any
+
+from fastapi import WebSocket
+
+
+class ConnectionManager:
+    def __init__(self) -> None:
+        # version_id -> list of active WebSocket connections
+        self._rooms: dict[str, list[WebSocket]] = {}
+
+    async def connect(self, version_id: uuid.UUID, websocket: WebSocket) -> None:
+        await websocket.accept()
+        key = str(version_id)
+        self._rooms.setdefault(key, []).append(websocket)
+
+    def disconnect(self, version_id: uuid.UUID, websocket: WebSocket) -> None:
+        key = str(version_id)
+        room = self._rooms.get(key, [])
+        if websocket in room:
+            room.remove(websocket)
+        if not room:
+            self._rooms.pop(key, None)
+
+    async def broadcast(self, version_id: uuid.UUID, event: str, data: Any) -> None:
+        key = str(version_id)
+        payload = json.dumps({"event": event, "data": data})
+        dead: list[WebSocket] = []
+        for ws in self._rooms.get(key, []):
+            try:
+                await ws.send_text(payload)
+            except Exception:
+                dead.append(ws)
+        for ws in dead:
+            self.disconnect(version_id, ws)
+
+    def room_size(self, version_id: uuid.UUID) -> int:
+        return len(self._rooms.get(str(version_id), []))
+
+
+manager = ConnectionManager()