Restructure data model: TrackingConfig + TemplateConfig entities

Major model restructuring for clean separation of concerns:

New entities:
- TrackingConfig: What to react to (event types, asset filters,
  periodic/scheduled/memory mode config) - reusable across targets
- TemplateConfig: All ~15 template slots from blueprint (event
  messages, asset formatting, date/location, scheduled messages)
  with full defaults - separate entities per locale

Changed entities:
- AlbumTracker: Simplified to album selection + polling + target_ids
  (removed event_types, template_id, all filter fields)
- NotificationTarget: Extended with tracking_config_id and
  template_config_id FKs (many-to-one, reusable configs)

Removed entities:
- MessageTemplate (replaced by TemplateConfig)
- ScheduledJob (absorbed into TrackingConfig)

Updated services:
- watcher.py: Each target checked against its own tracking_config
  for event filtering before sending notification
- notifier.py: Uses target's template_config to select the right
  template slot based on event type

New API routes:
- /api/tracking-configs/* (CRUD)
- /api/template-configs/* (CRUD + per-slot preview)

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

packages/server/src/immich_watcher_server/main.py

@@ -17,12 +17,12 @@ from .services.scheduler import start_scheduler, stop_scheduler
 from .auth.routes import router as auth_router
 from .api.servers import router as servers_router
 from .api.trackers import router as trackers_router
-from .api.templates import router as templates_router
+from .api.tracking_configs import router as tracking_configs_router
+from .api.template_configs import router as template_configs_router
 from .api.targets import router as targets_router
 from .api.users import router as users_router
 from .api.status import router as status_router
 from .api.sync import router as sync_router
-from .api.scheduled import router as scheduled_router
 from .ai.telegram_webhook import router as telegram_ai_router
 
 logging.basicConfig(
@@ -68,12 +68,12 @@ app.add_middleware(
 app.include_router(auth_router)
 app.include_router(servers_router)
 app.include_router(trackers_router)
-app.include_router(templates_router)
+app.include_router(tracking_configs_router)
+app.include_router(template_configs_router)
 app.include_router(targets_router)
 app.include_router(users_router)
 app.include_router(status_router)
 app.include_router(sync_router)
-app.include_router(scheduled_router)
 app.include_router(telegram_ai_router)
 
 # Serve frontend static files if available