Update gift cancellation to include received status

Allow cancellation of gifts with a status of either RESERVED or RECEIVED. This ensures consistency in handling gift statuses during reservation management across the application.

backend/app/crud/gift.py

@@ -136,7 +136,7 @@ class CRUDGiftItem(CRUDBase[GiftItem, GiftItemCreate, GiftItemUpdate]):
             raise ValueError(f"Guest with ID {guest_id} not found")
 
         # Only perform the operation if the gift is reserved
-        if gift.status == GiftStatus.RESERVED:
+        if gift.status in [GiftStatus.RESERVED, GiftStatus.RECEIVED]:
             # Check if this guest has actually reserved this gift
             if guest in gift.reserved_by:
                 gift.reserved_by.remove(guest)