- StoreReceivingRequest에 receiving_qty, receiving_date, lot_no 규칙 추가
- UpdateReceivingRequest status에 inspection_completed 허용 추가
- ReceivingService store()에 receiving_qty/date/lot_no 저장 처리
- order_qty null 안전 처리, 기본 status를 receiving_pending으로 변경
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>