Minor tweaks to sign up on frontend and database structure

backend/app/crud/shop_crud.py

@@ -31,7 +31,7 @@ def create_shop(session: Session, shop_data: ShopCreate, creator: User) -> None:
         description=shop_data.description,
         status=ShopStatus.INACTIVE,
         contact_email=creator.email,
-        phone_number=creator.phone_number,
+        contact_phone_number=creator.phone_number,
         currency=shop_data.currency
     )
     session.add(new_shop)