Translate to pt, fix some ui details, add proper icon and logo

src/services/loginApi.ts

@@ -0,0 +1,17 @@
+import { apiRequest } from '@/services/apiClient';
+
+type LoginResponse = {
+  authenticated: boolean;
+};
+
+export const loginApi = {
+  login(username: string, password: string) {
+    return apiRequest<LoginResponse>('/api/login', {
+      method: 'POST',
+      body: JSON.stringify({
+        username,
+        password,
+      }),
+    });
+  },
+};