如何将Firestore添加到我的Javascript代码？

// 引入Firebase SDK
<script src="https://www.gstatic.com/firebasejs/9.0.2/firebase-app.js"></script>
<script src="https://www.gstatic.com/firebasejs/9.0.2/firebase-firestore.js"></script>

// 初始化Firebase
<script>
  const config = {
    apiKey: "YOUR_API_KEY",
    authDomain: "YOUR_AUTH_DOMAIN",
    projectId: "YOUR_PROJECT_ID",
    storageBucket: "YOUR_STORAGE_BUCKET",
    messagingSenderId: "YOUR_MESSAGING_SENDER_ID",
    appId: "YOUR_APP_ID"
  };
  firebase.initializeApp(config);
</script>

// 添加Firestore模块
<script>
  const db = firebase.firestore();
</script>

// 使用Firestore
<script>
  // 读取数据
  db.collection("users").get().then((querySnapshot) => {
    querySnapshot.forEach((doc) => {
      console.log(`${doc.id} => ${doc.data()}`);
    });
  });

  // 写入数据
  db.collection("users").add({
    name: "John Doe",
    age: 30,
    email: "johndoe@example.com"
  }).then((docRef) => {
    console.log("Document written with ID: ", docRef.id);
  }).catch((error) => {
    console.error("Error adding document: ", error);
  });
</script>