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/lib/app-notify.ts

@@ -0,0 +1,13 @@
+export type AppNotifyType = 'success' | 'error' | 'warning';
+
+export interface AppNotifyDetail {
+  type: AppNotifyType;
+  text: string;
+}
+
+export const APP_NOTIFY_EVENT = 'nodewarden:notify';
+
+export function dispatchAppNotify(type: AppNotifyType, text: string): void {
+  if (typeof window === 'undefined') return;
+  window.dispatchEvent(new CustomEvent<AppNotifyDetail>(APP_NOTIFY_EVENT, { detail: { type, text } }));
+}