[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/ItemMasterDataManagement/dialogs/SectionDialog.tsx

@@ -0,0 +1,86 @@
+'use client';
+
+import { Dialog, DialogContent, DialogDescription, DialogFooter, DialogHeader, DialogTitle } from '@/components/ui/dialog';
+import { Button } from '@/components/ui/button';
+import { Label } from '@/components/ui/label';
+import { Input } from '@/components/ui/input';
+import { Textarea } from '@/components/ui/textarea';
+
+interface SectionDialogProps {
+  isSectionDialogOpen: boolean;
+  setIsSectionDialogOpen: (open: boolean) => void;
+  newSectionType: 'fields' | 'bom';
+  setNewSectionType: (type: 'fields' | 'bom') => void;
+  newSectionTitle: string;
+  setNewSectionTitle: (title: string) => void;
+  newSectionDescription: string;
+  setNewSectionDescription: (description: string) => void;
+  handleAddSection: () => void;
+}
+
+export function SectionDialog({
+  isSectionDialogOpen,
+  setIsSectionDialogOpen,
+  newSectionType,
+  setNewSectionType,
+  newSectionTitle,
+  setNewSectionTitle,
+  newSectionDescription,
+  setNewSectionDescription,
+  handleAddSection,
+}: SectionDialogProps) {
+  return (
+    <Dialog open={isSectionDialogOpen} onOpenChange={(open) => {
+      setIsSectionDialogOpen(open);
+      if (!open) {
+        setNewSectionType('fields');
+        setNewSectionTitle('');
+        setNewSectionDescription('');
+      }
+    }}>
+      <DialogContent className="max-w-[95vw] sm:max-w-[500px]">
+        <DialogHeader>
+          <DialogTitle>{newSectionType === 'bom' ? 'BOM 섹션' : '일반 섹션'} 추가</DialogTitle>
+          <DialogDescription>
+            {newSectionType === 'bom'
+              ? '새로운 BOM(자재명세서) 섹션을 추가합니다'
+              : '새로운 일반 섹션을 추가합니다'}
+          </DialogDescription>
+        </DialogHeader>
+        <div className="space-y-4">
+          <div>
+            <Label>섹션 제목 *</Label>
+            <Input
+              value={newSectionTitle}
+              onChange={(e) => setNewSectionTitle(e.target.value)}
+              placeholder={newSectionType === 'bom' ? '예: BOM 구성' : '예: 기본 정보'}
+            />
+          </div>
+          <div>
+            <Label>설명 (선택)</Label>
+            <Textarea
+              value={newSectionDescription}
+              onChange={(e) => setNewSectionDescription(e.target.value)}
+              placeholder="섹션에 대한 설명"
+            />
+          </div>
+          {newSectionType === 'bom' && (
+            <div className="bg-blue-50 p-3 rounded-md">
+              <p className="text-sm text-blue-700">
+                <strong>BOM 섹션:</strong> 자재명세서(BOM) 관리를 위한 전용 섹션입니다.
+                부품 구성, 수량, 단가 등을 관리할 수 있습니다.
+              </p>
+            </div>
+          )}
+        </div>
+        <DialogFooter className="flex-col sm:flex-row gap-2">
+          <Button variant="outline" onClick={() => {
+            setIsSectionDialogOpen(false);
+            setNewSectionType('fields');
+          }} className="w-full sm:w-auto">취소</Button>
+          <Button onClick={handleAddSection} className="w-full sm:w-auto">추가</Button>
+        </DialogFooter>
+      </DialogContent>
+    </Dialog>
+  );
+}