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-vue3/06-slots-and-provide-inject/starter.js

@@ -0,0 +1,27 @@
+const { createApp, provide, inject } = Vue;
+
+createApp({
+  components: {
+    ThemeCard: {
+      setup() {
+        const themeColor = inject("themeColor");
+
+        return {
+          themeColor,
+        };
+      },
+      template: `
+        <article class="card">
+          <h2>主题卡片</h2>
+          <button type="button" :style="{ background: themeColor }">
+            <slot>默认按钮</slot>
+          </button>
+        </article>
+      `,
+    },
+  },
+  setup() {
+    // 任务：通过 provide 提供 themeColor
+    return {};
+  },
+}).mount("#app");