feat: [outbound] 배차차량 관리 API — CRUD + options JSON 정책

- VehicleDispatchService: index(검색/필터/페이지네이션), stats(선불/착불/합계), show, update
- VehicleDispatchController + VehicleDispatchUpdateRequest
- options JSON 컬럼 추가 (dispatch_no, status, freight_cost_type, supply_amount, vat, total_amount, writer)
- ShipmentService.syncDispatches에 options 필드 지원 추가
- inventory.php에 vehicle-dispatches 라우트 4개 등록

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

app/Services/ShipmentService.php

@@ -513,6 +513,7 @@ protected function syncDispatches(Shipment $shipment, array $dispatches, int $te
                 'vehicle_no' => $dispatch['vehicle_no'] ?? null,
                 'driver_contact' => $dispatch['driver_contact'] ?? null,
                 'remarks' => $dispatch['remarks'] ?? null,
+                'options' => $dispatch['options'] ?? null,
             ]);
             $seq++;
         }