- Import encode_animation_cmd and ShowModel at module level
- Add show, fired_ids, is_playing per-connection state variables
- Extend load handler to load show from show_store by show_id (D-04)
- play handler sets is_playing=True
- pause handler sets is_playing=False without touching fired_ids
- seek handler rebuilds fired_ids from show cues before seek position (D-03)
- Add broadcast_loop sending position ticks at 10Hz to all clients
- Replace echo stub with play/pause/seek/load command dispatch to MPVEngine
- Start broadcast_loop as asyncio task in lifespan, cancel on shutdown
- Use get_engine callable to avoid circular import at module level
- DeviceRegistry with load/save/add/remove/instantiate and _DEVICE_CLASSES dict
- ShowStore with save/load/list_ids using aiofiles for async I/O
- FastAPI app with lifespan hook (startup: load registry/store, shutdown: save registry)
- API routes: GET/POST /api/devices/, DELETE /api/devices/{id}, GET/POST /api/shows/, GET /api/shows/{id}
- WebSocket stub at /ws with ConnectionManager and ack echo
- Frontend shell: DAW layout with header, sidebar (DEVICES + ANIMATIONS), TIMELINE, TRANSPORT
- Terminal aesthetic: dark theme, cyan accents, monospace fonts, no drop shadows
- .gitignore for runtime data (devices.json, shows/, __pycache__, .venv)