feat: enhance backup and download functionalities

- Updated `BackupCenterPage` to support download progress tracking during remote backup downloads.
- Modified `ImportPage` to simplify export functionality by removing unnecessary payload handling.
- Improved `JwtWarningPage` to utilize a new clipboard utility for copying text with feedback.
- Enhanced `PublicSendPage` to show download progress for files being downloaded.
- Updated `RecoverTwoFactorPage` to include autocomplete attributes for better user experience.
- Refactored `SendsPage` to use the new clipboard utility for copying access URLs.
- Enhanced `SettingsPage` to utilize the clipboard utility for copying sensitive information.
- Improved `TotpCodesPage` to use the clipboard utility for copying TOTP codes.
- Updated `VaultPage` and related components to support download progress for attachments.
- Introduced a new `app-notify` module for consistent notification handling across the application.
- Created a `clipboard` utility for improved clipboard interactions with user feedback.
- Added progress tracking for file downloads in the API layer, enhancing user experience during downloads.

webapp/src/components/AdminPage.tsx

@@ -1,5 +1,6 @@
 import { useState } from 'preact/hooks';
 import { ChevronLeft, ChevronRight, Clipboard, Plus, RefreshCw, Trash2, UserCheck, UserX } from 'lucide-preact';
+import { copyTextToClipboard } from '@/lib/clipboard';
 import type { AdminInvite, AdminUser } from '@/lib/types';
 import { t } from '@/lib/i18n';
 
@@ -134,7 +135,7 @@ export default function AdminPage(props: AdminPageProps) {
                     <button
                       type="button"
                       className="btn btn-secondary"
-                      onClick={() => navigator.clipboard.writeText(invite.inviteLink || '')}
+                      onClick={() => void copyTextToClipboard(invite.inviteLink || '', { successMessage: t('txt_link_copied') })}
                     >
                       <Clipboard size={14} className="btn-icon" /> {t('txt_copy_link')}
                     </button>