feat: implement user authentication with login functionality

- Add auth-api for handling login requests.
- Update index.ts to export AuthApi.
- Modify HeroLayout to display username or login link based on authentication state.
- Create LoginPage component for user login.
- Update router to include login route with EmptyLayout.
- Configure WebClient to include credentials in requests.
- Add auth-slice for managing authentication state in Redux.
- Update Redux store to include auth reducer.
- Define LoginRequest and User types in types/index.ts.
- Configure Vite to proxy API requests to the backend server.

vite.config.ts

@@ -12,4 +12,13 @@ export default defineConfig({
       "@": fileURLToPath(new URL("./src", import.meta.url)),
     },
   },
+  server: {
+    proxy: {
+      '/api': {
+        target: 'http://localhost:8080',
+        changeOrigin: true,
+        rewrite: (path) => path.replace(/^\/api/, '')
+      }
+    }
+  }
 })