refactor: 인벤토리 테이블 스펙과 도메인 계층 정비

lib/features/inventory/lookups/domain/entities/lookup_item.dart

@@ -0,0 +1,18 @@
+/// 공통 조회용 룩업 항목 엔티티.
+class LookupItem {
+  LookupItem({
+    required this.id,
+    required this.name,
+    this.code,
+    this.isDefault = false,
+    this.isActive = true,
+    this.note,
+  });
+
+  final int id;
+  final String? code;
+  final String name;
+  final bool isDefault;
+  final bool isActive;
+  final String? note;
+}