refactor(FR-3224): drop redundant announcement fetch in MaintenanceSettingList

The edit modal now fetches the announcement itself, so the Maintenance
page no longer needs to query get_announcement just to prefill the modal
(removing an extra suspending request on page load).

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Author: agatha197

react/src/components/MaintenanceSettingList.tsx

@@ -3,7 +3,6 @@
  Copyright (c) 2015-2026 Lablup Inc. All rights reserved.
  */
 import { useSuspendedBackendaiClient } from '../hooks';
-import { useSuspenseGetAnnouncement } from '../hooks/useAnnouncement';
 import { useSetBAINotification } from '../hooks/useBAINotification';
 import AnnouncementEditModal from './AnnouncementEditModal';
 import SettingList, { SettingGroup } from './SettingList';
@@ -23,8 +22,6 @@ const MaintenanceSettingList = () => {
   const { upsertNotification } = useSetBAINotification();
   const baiClient = useSuspendedBackendaiClient();
 
-  const { data: announcement } = useSuspenseGetAnnouncement();
-
   const recalculateUsage = () => {
     setIsRecalculating(true);
 
@@ -165,8 +162,6 @@ const MaintenanceSettingList = () => {
       <BAIUnmountAfterClose>
         <AnnouncementEditModal
           open={isAnnouncementModalOpen}
-          initialMessage={announcement?.message ?? ''}
-          initialEnabled={announcement?.enabled ?? true}
           onRequestClose={() => setIsAnnouncementModalOpen(false)}
         />
       </BAIUnmountAfterClose>