db0454d102
- Move all validation (packing, payment, status, duplicates) to CourierService::createShipmentForOrder() - Move database updates to service layer - Move document fetching to service layer - Simplify ShippingController to just handle HTTP concerns (request/response) - Simplify CreateShipmentOnReadyToShip listener to just dispatch events - Single source of truth for business logic in CourierService - Eliminates duplicate validation between controller and listener