feat: Import-API mit Vorschau, Saldo-Pruefung und Duplikat-Schutz

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

finance/app/main.py

@@ -5,13 +5,14 @@ from fastapi.responses import HTMLResponse, RedirectResponse
 
 from app import auth
 from app.config import get_settings
-from app.routers import accounts, categories, transactions
+from app.routers import accounts, categories, imports, transactions
 
 app = FastAPI(title="Finanzberatungs-Tool")
 
 app.include_router(accounts.router)
 app.include_router(transactions.router)
 app.include_router(categories.router)
+app.include_router(imports.router)
 
 
 @app.get("/login", response_class=HTMLResponse)