API and database models refactoring

app/services/stats_service.py

@@ -13,7 +13,8 @@ from typing import Any, Dict, List
 from sqlalchemy import func
 from sqlalchemy.orm import Session
 
-from models.database_models import Product, Stock
+from models.database.product import Product
+from models.database.stock import Stock
 
 logger = logging.getLogger(__name__)