Add enhanced models, scheduled jobs, per-locale templates (Phase 7b)

Backend changes for full blueprint feature parity:

Database models:
- MessageTemplate: add body_ru (locale variant), event_type field
- AlbumTracker: add track_images, track_videos, notify_favorites_only,
  include_people, include_asset_details, max_assets_to_show,
  assets_order_by, assets_order fields
- New ScheduledJob model: supports periodic_summary, scheduled_assets,
  and memory (On This Day) notification modes with full config
  (times, interval, album_mode, limit, filters, sorting)

API:
- New /api/scheduled/* CRUD endpoints for scheduled jobs
- Tracker create/update accept all new filtering fields
- Tracker response includes new fields

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

packages/server/src/immich_watcher_server/main.py

@@ -22,6 +22,7 @@ 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(
@@ -72,6 +73,7 @@ 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