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/Http/Requests/VehicleDispatch/VehicleDispatchUpdateRequest.php

@@ -0,0 +1,30 @@
+<?php
+
+namespace App\Http\Requests\VehicleDispatch;
+
+use Illuminate\Foundation\Http\FormRequest;
+
+class VehicleDispatchUpdateRequest extends FormRequest
+{
+    public function authorize(): bool
+    {
+        return true;
+    }
+
+    public function rules(): array
+    {
+        return [
+            'freight_cost_type' => 'nullable|in:prepaid,collect',
+            'logistics_company' => 'nullable|string|max:100',
+            'arrival_datetime' => 'nullable|date',
+            'tonnage' => 'nullable|string|max:20',
+            'vehicle_no' => 'nullable|string|max:20',
+            'driver_contact' => 'nullable|string|max:50',
+            'remarks' => 'nullable|string',
+            'supply_amount' => 'nullable|numeric|min:0',
+            'vat' => 'nullable|numeric|min:0',
+            'total_amount' => 'nullable|numeric|min:0',
+            'status' => 'nullable|in:draft,completed',
+        ];
+    }
+}