OSM-Beiträge: dog=yes-Erfassung mit GPS/Zeit-Anti-Fraud + Gamification-Zähler

- Tabelle osm_contributions (status pending→submitted→confirmed/rejected).
- Router /api/osm-contrib: POST /dog-friendly (Anti-Fraud: GPS-Beleg über
  kürzliche eigene Tour ≤50m + Verweil-Proxy, Tour-Recency 48h, Tages-Cap,
  Dedup, Positions-Sanity), GET /status (Zähler).
- Settings-UI: Zähler "X Orte eingetragen · noch Y bis Badge/Pro".
- OSM-Changeset-Upload + Pro-Freischaltung + Geräte-Attestierung folgen separat.

backend/main.py

@@ -228,6 +228,7 @@ from routes.events     import router as events_router
 from routes.sitting    import router as sitting_router
 from routes.osm        import router as osm_router
 from routes.osm_auth   import router as osm_auth_router
+from routes.osm_contrib import router as osm_contrib_router
 from routes.forum      import router as forum_router
 from routes.lost       import router as lost_router
 from routes.knigge     import router as knigge_router
@@ -294,6 +295,7 @@ app.include_router(events_router,     prefix="/api/events",     tags=["Events"])
 app.include_router(sitting_router,    prefix="/api/sitting",    tags=["Sitting"])
 app.include_router(osm_router,        prefix="/api/osm",        tags=["OSM"])
 app.include_router(osm_auth_router,   prefix="/api/osm-auth",   tags=["OSM-Auth"])
+app.include_router(osm_contrib_router, prefix="/api/osm-contrib", tags=["OSM-Beiträge"])
 app.include_router(weather_router,    prefix="/api/weather",    tags=["Wetter"])
 app.include_router(social_router,     prefix="/api/social",     tags=["Social"])
 app.include_router(forum_router,      prefix="/api/forum",      tags=["Forum"])