refactor(frontend): Begin modularizing work-report-calendar

Initiated the process of refactoring the monolithic `work-report-calendar.js` file as outlined in the Phase 2 frontend modernization plan.

- Created `CalendarAPI.js` to encapsulate all API calls related to the calendar, centralizing data fetching logic.
- Created `CalendarState.js` to manage the component's state, removing global variables from the main script.
- Refactored `work-report-calendar.js` to use the new state and API modules.
- Refactored `manage-project.js` to use the existing global API helpers, providing a consistent example for API usage.

web-ui/js/manage-project.js

@@ -1,9 +1,6 @@
 // /js/manage-project.js
 
-import { API, getAuthHeaders, ensureAuthenticated } from '/js/api-config.js';
-
-// 인증 확인
-ensureAuthenticated();
+// The ensureAuthenticated, API, and getAuthHeaders functions are now handled by the global api-helper.js
 
 function createRow(item, cols, delHandler) {
   const tr = document.createElement('tr');
@@ -40,13 +37,8 @@ projectForm?.addEventListener('submit', async e => {
   }
 
   try {
-    const res = await fetch(`${API}/projects`, {
-      method: 'POST',
-      headers: getAuthHeaders(),
-      body: JSON.stringify(body)
-    });
-    const result = await res.json();
-    if (res.ok && result.success) {
+    const result = await apiPost('/projects', body);
+    if (result.success) {
       alert('✅ 등록 완료');
       projectForm.reset();
       loadProjects();
@@ -62,34 +54,24 @@ async function loadProjects() {
   const tbody = document.getElementById('projectTableBody');
   tbody.innerHTML = '<tr><td colspan="9">불러오는 중...</td></tr>';
   try {
-    const res = await fetch(`${API}/projects`, {
-      headers: getAuthHeaders()
-    });
+    const result = await apiGet('/projects');
     
-    if (!res.ok) {
-      throw new Error(`HTTP error! status: ${res.status}`);
-    }
-    
-    const list = await res.json();
     tbody.innerHTML = '';
     
-    if (Array.isArray(list)) {
-      list.forEach(item => {
+    if (result.success && Array.isArray(result.data)) {
+      result.data.forEach(item => {
         const row = createRow(item, [
           'project_id', 'job_no', 'project_name', 'contract_date',
           'due_date', 'delivery_method', 'site', 'pm'
         ], async p => {
           if (!confirm('삭제하시겠습니까?')) return;
           try {
-            const delRes = await fetch(`${API}/projects/${p.project_id}`, {
-              method: 'DELETE',
-              headers: getAuthHeaders()
-            });
-            if (delRes.ok) {
+            const delRes = await apiDelete(`/projects/${p.project_id}`);
+            if (delRes.success) {
               alert('✅ 삭제 완료');
               loadProjects();
             } else {
-              alert('❌ 삭제 실패');
+              alert('❌ 삭제 실패: ' + (delRes.error || '알 수 없는 오류'));
             }
           } catch (err) {
             alert('🚨 삭제 중 오류: ' + err.message);