feat: Versionsanzeige (VERSION-Datei, Footer, /api/version, Image-Tag)

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

finance/app/routers/gui.py

@@ -21,8 +21,10 @@ from app.routers.planning import recurring_suggestions as _recurring_suggestions
 from app.routers.scenarios import list_scenarios as _list_scenarios
 from app.routers.transactions import list_transactions
 from app.services.balances import account_balance, total_balance
+from app.version import get_version
 
 templates = Jinja2Templates(directory="app/templates")
+templates.env.globals["app_version"] = get_version()
 router = APIRouter()