Navigation, Karten-FABs, Nearby-Alerts

- Bottom-Nav neu: Karte | Routen | + | Tagebuch | Forum
- + reduziert auf: Giftköder, Gassi-Treffen, Verlorener Hund
- Notification-Badge auf User-Avatar (Header)
- Nearby-Alerts: Nav-Leiste pulsiert rot/orange bei Giftköder/vermisstm Hund in 20km
- SW postMessage bei poison/lost_alert → sofortiger Alert-Check
- Karten-FABs: nur Marker setzen + Standort (Route aufzeichnen + Offline entfernt)
- SW by-v272, APP_VER 262

backend/main.py

@@ -93,6 +93,7 @@ from routes.import_data import router as import_router
 from routes.sharing    import dog_router as sharing_dog_router, share_router as sharing_share_router
 from routes.widget         import router as widget_router
 from routes.notifications  import router as notifications_router
+from routes.alerts         import router as alerts_router
 from routes.services       import router as services_router
 from routes.ratings        import router as ratings_router
 from routes.sitting_access import router as sitting_access_router
@@ -129,6 +130,7 @@ app.include_router(sharing_dog_router,     prefix="/api/dogs",    tags=["Teilen"
 app.include_router(sharing_share_router,   prefix="/api/share",   tags=["Teilen"])
 app.include_router(widget_router,          prefix="/api/widget",  tags=["Widget"])
 app.include_router(notifications_router,   prefix="/api/notifications", tags=["Notifications"])
+app.include_router(alerts_router,          prefix="/api/alerts",        tags=["Alerts"])
 app.include_router(services_router,        prefix="/api/services",      tags=["Services"])
 app.include_router(ratings_router,         prefix="/api/ratings",       tags=["Ratings"])
 app.include_router(sitting_access_router,  prefix="/api/sitting-access", tags=["SittingAccess"])