Add authentication system and admin panel

- Implement JWT-based authentication with login/logout
- Add user management routes and middleware
- Create admin panel for managing words and categories
- Add authentication store and API client
- Update database schema with User model
- Configure CORS and authentication middleware
- Add login page and protected routes

packages/frontend/vite.config.ts

@@ -11,6 +11,7 @@ export default defineConfig({
     },
   },
   server: {
+    host: '192.168.1.238',
     port: 5173,
     proxy: {
       '/api': {