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/backup-center/BackupDestinationDetail.tsx

@@ -27,6 +27,7 @@ interface BackupDestinationDetailProps {
   remoteBrowserTotalPages: number;
   loadingRemoteBrowser: boolean;
   downloadingRemotePath: string;
+  downloadingRemotePercent: number | null;
   restoringRemotePath: string;
   deletingRemotePath: string;
   onSaveSettings: () => void;
@@ -511,6 +512,7 @@ export function BackupDestinationDetail(props: BackupDestinationDetailProps) {
             currentPage={props.remoteBrowserCurrentPage}
             totalPages={props.remoteBrowserTotalPages}
             downloadingRemotePath={props.downloadingRemotePath}
+            downloadingRemotePercent={props.downloadingRemotePercent}
             restoringRemotePath={props.restoringRemotePath}
             deletingRemotePath={props.deletingRemotePath}
             onRefresh={props.onRefreshRemoteBrowser}

webapp/src/components/backup-center/RemoteBackupBrowser.tsx

@@ -13,6 +13,7 @@ interface RemoteBackupBrowserProps {
   currentPage: number;
   totalPages: number;
   downloadingRemotePath: string;
+  downloadingRemotePercent: number | null;
   restoringRemotePath: string;
   deletingRemotePath: string;
   onRefresh: () => void;
@@ -24,6 +25,13 @@ interface RemoteBackupBrowserProps {
 }
 
 export function RemoteBackupBrowser(props: RemoteBackupBrowserProps) {
+  const getDownloadLabel = (path: string) => {
+    if (props.downloadingRemotePath !== path) return t('txt_backup_remote_download');
+    return props.downloadingRemotePercent == null
+      ? t('txt_downloading')
+      : t('txt_downloading_percent', { percent: props.downloadingRemotePercent });
+  };
+
   return (
     <>
       <div className="backup-divider" />
@@ -98,7 +106,7 @@ export function RemoteBackupBrowser(props: RemoteBackupBrowserProps) {
                         <>
                           <button type="button" className="btn btn-secondary small" disabled={props.disableWhileBusy || props.downloadingRemotePath === item.path || !isZipCandidate(item)} onClick={() => props.onDownload(item.path)}>
                             <Download size={14} className="btn-icon" />
-                            {props.downloadingRemotePath === item.path ? t('txt_backup_remote_downloading') : t('txt_backup_remote_download')}
+                            {getDownloadLabel(item.path)}
                           </button>
                           <button type="button" className="btn btn-primary small" disabled={props.disableWhileBusy || props.restoringRemotePath === item.path || !isZipCandidate(item)} onClick={() => props.onRestore(item.path)}>
                             <RotateCcw size={14} className="btn-icon" />