Sprint 12: UI-Vereinheitlichung + Läufigkeits-Tracker

- by-tabs/by-tab: einheitliche Tab/Pill-Navigation in allen Seiten
- by-section-label, by-toolbar: einheitliche Section-Labels und Toolbars
- Design-Tokens: fehlende --c-amber, --c-primary-soft ergänzt, Fallback-Werte entfernt
- sitting.js: sitting-layout für konsistentes flush-Layout (wie walks)
- Läufigkeits-Tracker: neuer Health-Tab für Hündinnen mit Zyklusvorhersage,
  Timeline vergangener Läufigkeiten, Erinnerungen und auto-berechnetem Nächst-Datum
- emptyState-Bug: icon-Parameter muss SVG sein, nicht Icon-Name (dog/bell/warning gefixt)
- SW-Cache: by-v103, APP_VER: 79

backend/main.py

@@ -70,6 +70,7 @@ from routes.wiki       import router as wiki_router
 from routes.movies     import router as movies_router
 from routes.friends    import router as friends_router
 from routes.chat       import router as chat_router
+from routes.admin      import router as admin_router
 
 app.include_router(auth_router,       prefix="/api/auth",       tags=["Auth"])
 app.include_router(dogs_router,       prefix="/api/dogs",       tags=["Hunde"])
@@ -92,6 +93,7 @@ app.include_router(wiki_router,       prefix="/api/wiki",       tags=["Wiki"])
 app.include_router(movies_router,     prefix="/api/movies",     tags=["Filme"])
 app.include_router(friends_router,    prefix="/api/friends",    tags=["Freunde"])
 app.include_router(chat_router,       prefix="/api/chat",       tags=["Chat"])
+app.include_router(admin_router,      prefix="/api/admin",      tags=["Admin"])
 
 
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