Edit order line quantity

In the Edit Order screen, the store associate can either increase or decrease the quantity of an order line as required. When the order line quantity is changed, the Update button is enabled. When the store associate increases the ordered quantity and clicks the Update button, the getItemAvailabilityForStore API is called to retrieve the real-time availability of the product for the edited quantity. If the store associate reduces the ordered quantity, it is validated against the AvailableQtyForCancelAndStopDelivery attribute. If the required inventory is available, the modifyFulfillmentOptions API is called in the pending changes mode to update the entered quantity. The getCompleteOrderDetails API is called to refresh the screen with a message indicating the updated order total and the due payment or refund for the order. When the store associate clicks Save, the changeOrder API is called to commit the changes to the database.