[feat]: Item Master 데이터 관리 기능 구현 및 타입 에러 수정

- ItemMasterDataManagement 컴포넌트 구조화 (tabs, dialogs, components 분리)
- HierarchyTab 타입 에러 수정 (BOMItem section_id, updated_at 추가)
- API 클라이언트 구현 (item-master.ts, 13개 엔드포인트)
- ItemMasterContext 구현 (상태 관리 및 데이터 흐름)
- 백엔드 요구사항 문서 작성 (CORS 설정, API 스펙 등)
- SSR 호환성 수정 (navigator API typeof window 체크)
- 미사용 변수 ESLint 에러 해결
- Context 리팩토링 (AuthContext, RootProvider 추가)
- API 유틸리티 추가 (error-handler, logger, transformers)

🤖 Generated with Claude Code

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

src/components/items/BOMManagementSection.tsx

@@ -10,25 +10,15 @@ import { Card, CardContent, CardDescription, CardHeader, CardTitle } from '@/com
 import { Badge } from '@/components/ui/badge';
 import { Plus, Edit, Trash2, Package, GripVertical } from 'lucide-react';
 import { toast } from 'sonner';
-
-export interface BOMItem {
-  id: string;
-  itemCode: string;
-  itemName: string;
-  quantity: number;
-  unit: string;
-  itemType?: string;
-  note?: string;
-  createdAt: string;
-}
+import type { BOMItem } from '@/contexts/ItemMasterContext';
 
 interface BOMManagementSectionProps {
   title?: string;
   description?: string;
   bomItems: BOMItem[];
-  onAddItem: (item: Omit<BOMItem, 'id' | 'createdAt'>) => void;
-  onUpdateItem: (id: string, item: Partial<BOMItem>) => void;
-  onDeleteItem: (id: string) => void;
+  onAddItem: (item: Omit<BOMItem, 'id' | 'createdAt' | 'created_at' | 'updated_at' | 'tenant_id' | 'section_id'>) => void;
+  onUpdateItem: (id: number, item: Partial<BOMItem>) => void;
+  onDeleteItem: (id: number) => void;
   itemTypeOptions?: { value: string; label: string }[];
   unitOptions?: { value: string; label: string }[];
 }
@@ -53,7 +43,7 @@ export function BOMManagementSection({
   ],
 }: BOMManagementSectionProps) {
   const [isDialogOpen, setIsDialogOpen] = useState(false);
-  const [editingId, setEditingId] = useState<string | null>(null);
+  const [editingId, setEditingId] = useState<number | null>(null);
   const [itemCode, setItemCode] = useState('');
   const [itemName, setItemName] = useState('');
   const [quantity, setQuantity] = useState('1');
@@ -64,12 +54,12 @@ export function BOMManagementSection({
   const handleOpenDialog = (item?: BOMItem) => {
     if (item) {
       setEditingId(item.id);
-      setItemCode(item.itemCode);
-      setItemName(item.itemName);
+      setItemCode(item.item_code || '');
+      setItemName(item.item_name);
       setQuantity(item.quantity.toString());
-      setUnit(item.unit);
-      setItemType(item.itemType || 'part');
-      setNote(item.note || '');
+      setUnit(item.unit || 'EA');
+      setItemType('part');
+      setNote(item.spec || '');
     } else {
       setEditingId(null);
       setItemCode('');
@@ -93,12 +83,11 @@ export function BOMManagementSection({
     }
 
     const itemData = {
-      itemCode,
-      itemName,
+      item_code: itemCode,
+      item_name: itemName,
       quantity: qty,
       unit,
-      itemType,
-      note: note.trim() || undefined,
+      spec: note.trim() || undefined,
     };
 
     if (editingId) {
@@ -112,7 +101,7 @@ export function BOMManagementSection({
     setIsDialogOpen(false);
   };
 
-  const handleDelete = (id: string) => {
+  const handleDelete = (id: number) => {
     if (confirm('이 BOM 품목을 삭제하시겠습니까?')) {
       onDeleteItem(id);
       toast.success('BOM 품목이 삭제되었습니다');
@@ -159,19 +148,16 @@ export function BOMManagementSection({
                   <div className="flex-1">
                     <div className="flex items-center gap-2">
                       <GripVertical className="h-4 w-4 text-gray-400" />
-                      <span className="font-medium">{item.itemName}</span>
-                      <Badge variant="outline" className="text-xs">
-                        {item.itemCode}
-                      </Badge>
-                      {item.itemType && (
-                        <Badge variant="secondary" className="text-xs">
-                          {itemTypeOptions.find((t) => t.value === item.itemType)?.label || item.itemType}
+                      <span className="font-medium">{item.item_name}</span>
+                      {item.item_code && (
+                        <Badge variant="outline" className="text-xs">
+                          {item.item_code}
                         </Badge>
                       )}
                     </div>
                     <div className="ml-6 text-sm text-gray-500 mt-1">
-                      수량: {item.quantity} {item.unit}
-                      {item.note && <span className="ml-2">• {item.note}</span>}
+                      수량: {item.quantity} {item.unit || 'EA'}
+                      {item.spec && <span className="ml-2">• {item.spec}</span>}
                     </div>
                   </div>
                   <div className="flex gap-2">