feat: Add Vue3 exercises and interview plan

- Introduced Vue3 exercises covering composable API, reactivity, lifecycle hooks, and built-in components.
- Added structured interview plan for frontend candidates focusing on HTML, CSS, JavaScript, TypeScript, and Vue.
- Included starter files for each exercise and detailed README documentation for guidance.

08-vue3/04-lifecycle-and-template-ref/starter.js

@@ -0,0 +1,28 @@
+const { createApp, ref, onMounted, onUpdated, onUnmounted } = Vue;
+
+createApp({
+  setup() {
+    const keyword = ref("");
+    const keywordInput = ref(null);
+    let timer = null;
+
+    onMounted(() => {
+      // 任务：
+      // 1. 让输入框自动聚焦
+      // 2. 建立一个定时器
+    });
+
+    onUpdated(() => {
+      // 任务：输出 updated 日志
+    });
+
+    onUnmounted(() => {
+      // 任务：清理定时器并输出销毁日志
+    });
+
+    return {
+      keyword,
+      keywordInput,
+    };
+  },
+}).mount("#app");