Add user data synchronization and database IPC handlers

- Introduce `db:user:sync` to synchronize user data with the local database during initialization.
- Add `db:user:info` and `db:user:update` IPC handlers for fetching and updating user information.
- Update `User` model and repository to support extended user fields and improved structure.
- Dynamically import user models in main process to avoid circular dependencies.
- Refactor database initialization in the app to include user sync logic with error handling.

electron/main.ts

@@ -8,6 +8,7 @@ import { getDatabaseService } from './database/database.service.js';
 
 // Import IPC handlers
 import './ipc/book.ipc.js';
+import './ipc/user.ipc.js';
 
 // Fix pour __dirname en ES modules
 const __filename = fileURLToPath(import.meta.url);
@@ -169,6 +170,52 @@ ipcMain.on('logout', () => {
   createLoginWindow();
 });
 
+// ========== USER SYNC (PRE-AUTHENTICATION) ==========
+
+interface SyncUserData {
+  userId: string;
+  firstName: string;
+  lastName: string;
+  username: string;
+  email: string;
+}
+
+ipcMain.handle('db:user:sync', async (_event, data: SyncUserData): Promise<boolean> => {
+  try {
+    // Import User models dynamically to avoid circular dependencies
+    const { default: User } = await import('./database/models/User.js');
+    const { default: UserRepo } = await import('./database/repositories/user.repository.js');
+
+    const lang: 'fr' | 'en' = 'fr';
+
+    // Check if user already exists in local DB
+    try {
+      UserRepo.fetchUserInfos(data.userId, lang);
+      // User exists, no need to sync
+      console.log(`[DB] User ${data.userId} already exists in local DB, skipping sync`);
+      return true;
+    } catch (error) {
+      // User doesn't exist, create it
+      console.log(`[DB] User ${data.userId} not found, creating in local DB`);
+
+      await User.addUser(
+        data.userId,
+        data.firstName,
+        data.lastName,
+        data.username,
+        data.email,
+        '', // Password not needed for local DB
+        lang
+      );
+      console.log(`[DB] User ${data.userId} synced successfully`);
+      return true;
+    }
+  } catch (error) {
+    console.error('[DB] Failed to sync user:', error);
+    throw error;
+  }
+});
+
 // ========== DATABASE IPC HANDLERS ==========
 
 /**