fix(calendar): Add cache-busting and better error handling

- Added cache: 'no-store' to prevent cached 500 errors
- Enhanced error messages with status codes
- Display detailed error messages to user
- Log API response text for debugging
- Helps diagnose mobile loading issues

public/js/admin/calendar.js

@@ -100,10 +100,15 @@
     try {
       const token = localStorage.getItem('admin_token');
       const response = await fetch('/api/calendar/stats', {
+        cache: 'no-store',
         headers: { 'Authorization': `Bearer ${token}` }
       });
 
-      if (!response.ok) throw new Error('Failed to load stats');
+      if (!response.ok) {
+        const errorText = await response.text();
+        console.error('Stats API error:', response.status, errorText);
+        throw new Error(`Failed to load stats: ${response.status}`);
+      }
 
       const data = await response.json();
       const stats = data.stats;
@@ -116,7 +121,7 @@
 
     } catch (error) {
       console.error('Error loading stats:', error);
-      showError('Failed to load statistics');
+      showError('Failed to load statistics: ' + error.message);
     }
   }
 
@@ -137,10 +142,15 @@
       if (currentFilters.includeCompleted) params.append('includeCompleted', 'true');
 
       const response = await fetch(`/api/calendar/tasks?${params}`, {
+        cache: 'no-store',
         headers: { 'Authorization': `Bearer ${token}` }
       });
 
-      if (!response.ok) throw new Error('Failed to load tasks');
+      if (!response.ok) {
+        const errorText = await response.text();
+        console.error('Tasks API error:', response.status, errorText);
+        throw new Error(`Failed to load tasks: ${response.status}`);
+      }
 
       const data = await response.json();
       allTasks = data.tasks;
@@ -152,7 +162,8 @@
       console.error('Error loading tasks:', error);
       tasksContainer.innerHTML = `
         <div class="text-center py-12 text-red-600">
-          <p>Failed to load tasks. Please try again.</p>
+          <p>Failed to load tasks: ${error.message}</p>
+          <p class="text-sm mt-2">Check console for details</p>
         </div>
       `;
     }