Feature: 3 Community-Features — Foto-Challenge, Stamm-Gassis, Rassen-Chip (SW by-v700)

- Foto-Challenge der Woche: DB-Tabellen, routes/challenges.py (current/submit/vote/winners),
  Scheduler-Job jeden Montag 08:00, walks.js Challenge-Tab mit Banner, Galerie, Voting-Herz
- Gassi-Zeiten-Pool: DB-Tabelle gassi_zeiten, routes/gassi_zeiten.py (CRUD + Umkreis),
  walks.js Stamm-Gassis-Tab mit Karten, Wochentag-Selector, Mitmachen→Chat
- Rassen-Treffen-Chip: GET /api/friends/same-breed, dog-profile.js zeigt Chip
  wenn andere User gleiche Rasse haben, Klick → Forum mit Rassen-Suche vorausgefüllt

backend/main.py

@@ -233,6 +233,8 @@ from routes.health_docs    import router as health_docs_router
 from routes.passport       import router as passport_router
 from routes.playdate       import router as playdate_router
 from routes.ernaehrung     import router as ernaehrung_router
+from routes.challenges     import router as challenges_router
+from routes.gassi_zeiten   import router as gassi_zeiten_router
 
 app.include_router(auth_router,       prefix="/api/auth",       tags=["Auth"])
 app.include_router(dogs_router,       prefix="/api/dogs",       tags=["Hunde"])
@@ -292,6 +294,8 @@ app.include_router(health_docs_router,     prefix="/api/health-docs",          t
 app.include_router(passport_router,        prefix="/api/passport",             tags=["Hundepass"])
 app.include_router(playdate_router,        prefix="/api/playdate",            tags=["Playdate"])
 app.include_router(ernaehrung_router,     prefix="/api/dogs",                tags=["Ernährung"])
+app.include_router(challenges_router,     prefix="/api/challenges",           tags=["Foto-Challenge"])
+app.include_router(gassi_zeiten_router,   prefix="/api/gassi-zeiten",         tags=["Gassi-Zeiten"])
 
 
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