fix(calendar): resolve infinite loading on manage calendar button

- Removed duplicate modal opening via data-bs-toggle attribute
- Changed to programmatic opening via openForCreate() only
- Added calendar:edit event listener for edit functionality
- Updated button selector from data-bs-target to data-action

Issue: Button had both Bootstrap modal trigger and JS event listener,
causing double initialization and infinite loading state.

Solution: Use only programmatic modal opening through calendarManageModal API.

backend/static/js/components/calendarWidgetIntegration.js

@@ -180,13 +180,22 @@ export function integrateCalendarManager(calendarWidgetInstance, options = {}) {
   });
 
   // Привязываем кнопку создания календаря к модальному окну
-  const createCalendarBtn = document.querySelector('[data-bs-target="#calendarManageModal"]');
+  const createCalendarBtn = document.querySelector('[data-action="create-calendar"]');
   if (createCalendarBtn && manageModalInstance) {
     createCalendarBtn.addEventListener('click', () => {
       manageModalInstance.openForCreate();
     });
   }
 
+  // Обрабатываем событие редактирования календаря из списка
+  if (manageModalInstance) {
+    document.addEventListener('calendar:edit', (e) => {
+      const calendar = e.detail;
+      console.log('[CalendarIntegration] Edit calendar requested:', calendar);
+      manageModalInstance.openForEdit(calendar.id);
+    });
+  }
+
   // Создаём объект интеграции
   const integration = {
     /**

backend/templates/includes/components/calendar_desktop.html

@@ -25,8 +25,7 @@
         <button 
           class="btn btn-sm btn-outline-primary" 
           type="button" 
-          data-bs-toggle="modal" 
-          data-bs-target="#calendarManageModal"
+          data-action="create-calendar"
           aria-label="Создать календарь"
           title="Создать календарь"
         >