fix: [items] 품목 규격 accessor + 감사로그 + bom_category 마이그레이션

- Item 모델에 specification accessor 추가 (attributes.spec 조회)
- ItemService.update()에 AuditLogger 감사 로그 추가
- items.options에 bom_category 추가 마이그레이션

database/migrations/2026_03_16_185842_add_bom_category_to_items_options.php

@@ -0,0 +1,90 @@
+<?php
+
+use Illuminate\Database\Migrations\Migration;
+use Illuminate\Support\Facades\DB;
+
+/**
+ * 품목 options JSON에 bom_category 필드 일괄 추가
+ *
+ * BOM 카테고리: material, motor, controller, steel, parts, inspection
+ * 매핑 규칙:
+ *   - EST-RAW-*     → material (주자재)
+ *   - RM (원자재)    → material
+ *   - EST-MOTOR-*   → motor (모터)
+ *   - EST-CTRL-*    → controller (제어기)
+ *   - BD-* (BENDING) → steel (절곡품)
+ *   - EST-INSPECTION → inspection (검사비)
+ *   - CS (소모품)    → inspection
+ *   - 나머지 PT/SM   → parts (부자재)
+ */
+return new class extends Migration
+{
+    public function up(): void
+    {
+        // 1. material: EST-RAW-* 코드
+        DB::table('items')
+            ->where('code', 'like', 'EST-RAW-%')
+            ->update([
+                'options' => DB::raw("JSON_SET(COALESCE(options, '{}'), '$.bom_category', 'material')"),
+            ]);
+
+        // 2. material: RM (원자재) 타입
+        DB::table('items')
+            ->where('item_type', 'RM')
+            ->update([
+                'options' => DB::raw("JSON_SET(COALESCE(options, '{}'), '$.bom_category', 'material')"),
+            ]);
+
+        // 3. motor: EST-MOTOR-* 코드
+        DB::table('items')
+            ->where('code', 'like', 'EST-MOTOR-%')
+            ->update([
+                'options' => DB::raw("JSON_SET(COALESCE(options, '{}'), '$.bom_category', 'motor')"),
+            ]);
+
+        // 4. controller: EST-CTRL-* 코드
+        DB::table('items')
+            ->where('code', 'like', 'EST-CTRL-%')
+            ->update([
+                'options' => DB::raw("JSON_SET(COALESCE(options, '{}'), '$.bom_category', 'controller')"),
+            ]);
+
+        // 5. steel: item_category=BENDING (BD-* 코드)
+        DB::table('items')
+            ->where('item_category', 'BENDING')
+            ->update([
+                'options' => DB::raw("JSON_SET(COALESCE(options, '{}'), '$.bom_category', 'steel')"),
+            ]);
+
+        // 6. inspection: EST-INSPECTION 코드
+        DB::table('items')
+            ->where('code', 'EST-INSPECTION')
+            ->update([
+                'options' => DB::raw("JSON_SET(COALESCE(options, '{}'), '$.bom_category', 'inspection')"),
+            ]);
+
+        // 7. inspection: CS (소모품) 타입
+        DB::table('items')
+            ->where('item_type', 'CS')
+            ->update([
+                'options' => DB::raw("JSON_SET(COALESCE(options, '{}'), '$.bom_category', 'inspection')"),
+            ]);
+
+        // 8. parts: 나머지 PT/SM (아직 bom_category가 없는 것)
+        DB::table('items')
+            ->whereIn('item_type', ['PT', 'SM'])
+            ->whereRaw("(options IS NULL OR JSON_EXTRACT(options, '$.bom_category') IS NULL)")
+            ->update([
+                'options' => DB::raw("JSON_SET(COALESCE(options, '{}'), '$.bom_category', 'parts')"),
+            ]);
+    }
+
+    public function down(): void
+    {
+        DB::table('items')
+            ->whereRaw("JSON_EXTRACT(options, '$.bom_category') IS NOT NULL")
+            ->update([
+                'options' => DB::raw("JSON_REMOVE(options, '$.bom_category')"),
+            ]);
+    }
+};