feat: integrate Firebase for authentication and data management, add GameItem type, and enhance UI with tooltips

src/services/auth/auth.ts

@@ -0,0 +1,40 @@
+import {
+  signInWithEmailAndPassword,
+  createUserWithEmailAndPassword,
+  signOut as firebaseSignOut,
+  User,
+  GoogleAuthProvider,
+  signInWithPopup
+} from 'firebase/auth';
+import { auth } from '../../config/firebase';
+
+export async function login(email: string, password: string): Promise<string> {
+  const userCredential = await signInWithEmailAndPassword(auth, email, password);
+  const token = await userCredential.user.getIdToken();
+  localStorage.setItem('TOKEN', token);
+  return token;
+}
+
+export async function register(email: string, password: string): Promise<string> {
+  const userCredential = await createUserWithEmailAndPassword(auth, email, password);
+  const token = await userCredential.user.getIdToken();
+  localStorage.setItem('TOKEN', token);
+  return token;
+}
+
+export async function signOut(): Promise<void> {
+  await firebaseSignOut(auth);
+  localStorage.removeItem('TOKEN');
+}
+
+export function getCurrentUser(): User | null {
+  return auth.currentUser;
+}
+
+export async function signInWithGoogle(): Promise<string> {
+  const provider = new GoogleAuthProvider();
+  const userCredential = await signInWithPopup(auth, provider);
+  const token = await userCredential.user.getIdToken();
+  localStorage.setItem('TOKEN', token);
+  return token;
+}