fix: MES 모델 및 서비스 개선

- WorkOrderItem 모델 관계 정의 추가
- InspectionService, WorkResultService 로직 개선
- ItemReceipt, Inspection 모델 수정
- work_order_items 테이블에 options 컬럼 추가 마이그레이션

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

database/migrations/2026_01_14_155354_add_options_to_work_order_items_table.php

@@ -0,0 +1,28 @@
+<?php
+
+use Illuminate\Database\Migrations\Migration;
+use Illuminate\Database\Schema\Blueprint;
+use Illuminate\Support\Facades\Schema;
+
+return new class extends Migration
+{
+    /**
+     * Run the migrations.
+     */
+    public function up(): void
+    {
+        Schema::table('work_order_items', function (Blueprint $table) {
+            $table->json('options')->nullable()->after('status')->comment('작업 결과 등 추가 정보 (JSON)');
+        });
+    }
+
+    /**
+     * Reverse the migrations.
+     */
+    public function down(): void
+    {
+        Schema::table('work_order_items', function (Blueprint $table) {
+            $table->dropColumn('options');
+        });
+    }
+};