feat(migration): enforce ownerId requirement in Product table

- Removed all products without an owner to maintain data integrity.
- Updated ownerId column to be non-nullable.
- Modified foreign key constraint for ownerId to use ON DELETE CASCADE.

backend/src/receipt-import/receipt-import.controller.ts

@@ -49,6 +49,7 @@ export class ReceiptImportController {
       );
     }
     const isPremium = req?.user?.isPremium === true || req?.user?.role === 'admin';
-    return this.receiptImportService.parseReceipt(file, isPremium);
+    const userId = typeof req?.user?.id === 'number' ? req.user.id : undefined;
+    return this.receiptImportService.parseReceipt(file, isPremium, userId);
   }
 }