Add auto-update functionality for Electron app

- Integrated `electron-updater` dependency for managing app updates.
- Configured publishing settings with a generic provider and download URL.
- Added `initAutoUpdater` method to handle app updates and implemented it in the main process.
- Updated `package.json` and `package-lock.json` to include `electron-updater` and related dependencies.

electron/main.ts

@@ -6,6 +6,7 @@ import {DatabaseService, getDatabaseService} from './database/database.service.j
 import SecureStorage, {getSecureStorage} from './storage/SecureStorage.js';
 import {getUserEncryptionKey, hasUserEncryptionKey, setUserEncryptionKey} from './database/keyManager.js';
 import {generateUserEncryptionKey} from './database/encryption.js';
+import {initAutoUpdater} from './autoUpdater.js';
 
 // Import IPC handlers
 import './ipc/book.ipc.js';
@@ -144,6 +145,7 @@ function createMainWindow(): void {
 
   mainWindow.once('ready-to-show', () => {
     mainWindow?.show();
+    initAutoUpdater(mainWindow);
   });
 
   mainWindow.on('closed', () => {