feat: fetchWrapper 마이그레이션 및 토큰 리프레시 캐싱 구현

- 40+ actions.ts 파일을 fetchWrapper 패턴으로 마이그레이션
- 토큰 리프레시 캐싱 로직 추가 (refresh-token.ts)
- ApiErrorContext 추가로 전역 에러 처리 개선
- HR EmployeeForm 컴포넌트 개선
- 참조함(ReferenceBox) 기능 수정
- juil 테스트 URL 페이지 추가
- claudedocs 문서 업데이트

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

src/components/settings/NotificationSettings/actions.ts

@@ -1,42 +1,36 @@
 'use server';
 
-import { cookies } from 'next/headers';
+import { serverFetch } from '@/lib/api/fetch-wrapper';
 import type { NotificationSettings } from './types';
 import { DEFAULT_NOTIFICATION_SETTINGS } from './types';
 
-// ===== API 헤더 생성 =====
-async function getApiHeaders(): Promise<HeadersInit> {
-  const cookieStore = await cookies();
-  const token = cookieStore.get('access_token')?.value;
-
-  return {
-    'Accept': 'application/json',
-    'Content-Type': 'application/json',
-    'Authorization': token ? `Bearer ${token}` : '',
-    'X-API-KEY': process.env.API_KEY || '',
-  };
-}
-
 // ===== 알림 설정 조회 =====
 export async function getNotificationSettings(): Promise<{
   success: boolean;
   data: NotificationSettings;
   error?: string;
+  __authError?: boolean;
 }> {
   try {
-    const headers = await getApiHeaders();
-
-    const response = await fetch(
+    const { response, error } = await serverFetch(
       `${process.env.NEXT_PUBLIC_API_URL}/api/v1/settings/notifications`,
       {
         method: 'GET',
-        headers,
         cache: 'no-store',
       }
     );
 
-    if (!response.ok) {
-      console.warn('[NotificationActions] GET settings error:', response.status);
+    if (error) {
+      return {
+        success: false,
+        data: DEFAULT_NOTIFICATION_SETTINGS,
+        error: error.message,
+        __authError: error.code === 'UNAUTHORIZED',
+      };
+    }
+
+    if (!response || !response.ok) {
+      console.warn('[NotificationActions] GET settings error:', response?.status);
       return {
         success: true,
         data: DEFAULT_NOTIFICATION_SETTINGS,
@@ -69,20 +63,33 @@ export async function getNotificationSettings(): Promise<{
 // ===== 알림 설정 저장 =====
 export async function saveNotificationSettings(
   settings: NotificationSettings
-): Promise<{ success: boolean; error?: string }> {
+): Promise<{ success: boolean; error?: string; __authError?: boolean }> {
   try {
-    const headers = await getApiHeaders();
     const apiData = transformFrontendToApi(settings);
 
-    const response = await fetch(
+    const { response, error } = await serverFetch(
       `${process.env.NEXT_PUBLIC_API_URL}/api/v1/settings/notifications`,
       {
         method: 'PUT',
-        headers,
         body: JSON.stringify(apiData),
       }
     );
 
+    if (error) {
+      return {
+        success: false,
+        error: error.message,
+        __authError: error.code === 'UNAUTHORIZED',
+      };
+    }
+
+    if (!response) {
+      return {
+        success: false,
+        error: '알림 설정 저장에 실패했습니다.',
+      };
+    }
+
     const result = await response.json();
 
     if (!response.ok || !result.success) {