feat: add schedulers feature with task management

- Introduced SchedulersPage for managing scheduled tasks.
- Implemented CreateTaskDialog for creating new scheduled tasks.
- Added SchedulersHeader for filtering and searching tasks.
- Created SchedulersTable to display scheduled tasks with actions.
- Implemented loading and error states with SchedulersLoadingStates.
- Added API service for task management in schedulers.
- Enhanced date formatting utility to handle timezone.
- Updated AppSidebar and AppRoutes to include SchedulersPage.

src/App.tsx

@@ -12,6 +12,7 @@ import { LoginPage } from './pages/LoginPage'
 import { PlaylistEditPage } from './pages/PlaylistEditPage'
 import { PlaylistsPage } from './pages/PlaylistsPage'
 import { RegisterPage } from './pages/RegisterPage'
+import { SchedulersPage } from './pages/SchedulersPage'
 import { SoundsPage } from './pages/SoundsPage'
 import { SettingsPage } from './pages/admin/SettingsPage'
 import { UsersPage } from './pages/admin/UsersPage'
@@ -110,6 +111,14 @@ function AppRoutes() {
           </ProtectedRoute>
         }
       />
+      <Route
+        path="/schedulers"
+        element={
+          <ProtectedRoute>
+            <SchedulersPage />
+          </ProtectedRoute>
+        }
+      />
       <Route
         path="/account"
         element={