Sprint 8: Events + Hundesitting

Events:
- Backend events.py: CRUD, Typen (ausstellung/training/treffen/markt/wettkampf/sonstiges)
  Haversine-Filter, Monats-Gruppierung in der Liste
- Frontend events.js: Liste/Karte-Toggle, Typ-Filter-Chips, farbige Marker,
  Detail-Modal, Erstellen/Bearbeiten-Formular mit GPS-Button

Hundesitting:
- Backend sitting.py: Sitter-Profile (create/update/me), Anfragen (send/accept/decline/cancel),
  Inbox für Sitter, Haversine-Sortierung, Service-Filter
- Frontend sitting.js: 3 Tabs (Suchen/Profil/Anfragen), Sitter-Karten mit Distanz,
  Detail-Modal + Anfrage-Formular, Profil-Verwaltung

DB: events, sitters, sitting_requests Tabellen hinzugefügt
SW-Cache: by-v21 → by-v22

backend/main.py

@@ -60,6 +60,8 @@ from routes.tieraerzte import router as tieraerzte_router
 from routes.places     import router as places_router
 from routes.routen     import router as routen_router
 from routes.walks      import router as walks_router
+from routes.events     import router as events_router
+from routes.sitting    import router as sitting_router
 
 app.include_router(auth_router,       prefix="/api/auth",       tags=["Auth"])
 app.include_router(dogs_router,       prefix="/api/dogs",       tags=["Hunde"])
@@ -72,6 +74,8 @@ app.include_router(tieraerzte_router, prefix="/api/tieraerzte", tags=["Tierärzt
 app.include_router(places_router,     prefix="/api/places",     tags=["Orte"])
 app.include_router(routen_router,     prefix="/api/routes",     tags=["Routen"])
 app.include_router(walks_router,      prefix="/api/walks",      tags=["Gassi-Treffen"])
+app.include_router(events_router,     prefix="/api/events",     tags=["Events"])
+app.include_router(sitting_router,    prefix="/api/sitting",    tags=["Sitting"])
 
 
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