Feature: Partner-Codes + Gründer-Lizenz-System für Influencer-Kooperationen

- partner_codes Tabelle: Code, Label, max_uses, grants_founder, uses-Counter
- users: is_founder + is_partner Flags (DB-Migration + auth.py SELECT)
- Registrierung: Partner-Code löst Gründer-Lizenz aus (vor User-Referral geprüft)
- API: GET/POST/DELETE /api/admin/partner/codes, POST /api/admin/partner/users/{id}/grant
- API: GET /api/partner/codes/{code}/info (öffentlich, für Registrierungsvalidierung)
- API: GET /api/admin/users/search (Name-Suche für Admin-UI)
- Admin-Tab "Partner & Codes": Code anlegen, Stats, User-Status vergeben
- Registrierungsformular: Einladungscode-Feld mit Live-Validierung
- Settings: Gründer (lila) + Partner (blau) Badge neben Kostenlos/Plus
- SW by-v515, APP_VER 492

backend/main.py

@@ -162,6 +162,7 @@ from routes.breeder_photos import router as breeder_photos_router
 from routes.zucht_hunde    import router as zucht_hunde_router
 from routes.breeder_export import router as breeder_export_router
 from routes.zucht_ki       import router as zucht_ki_router
+from routes.partner        import router as partner_router
 
 app.include_router(auth_router,       prefix="/api/auth",       tags=["Auth"])
 app.include_router(dogs_router,       prefix="/api/dogs",       tags=["Hunde"])
@@ -193,6 +194,7 @@ app.include_router(breeder_photos_router,  prefix="/api",       tags=["Züchter-
 app.include_router(zucht_hunde_router,     prefix="/api",       tags=["Zuchtkartei"])
 app.include_router(breeder_export_router,  prefix="/api",       tags=["Export"])
 app.include_router(zucht_ki_router,        prefix="/api",       tags=["Züchter-KI"])
+app.include_router(partner_router,         prefix="/api",       tags=["Partner"])
 app.include_router(webcal_router,     prefix="/api/webcal",     tags=["WebCal"])
 app.include_router(profile_router,    prefix="/api/profile",    tags=["Profil"])
 app.include_router(import_router,          prefix="/api/import",  tags=["Import"])