feat: 添加示例刷新按钮

- 在示例标题旁添加刷新按钮
   - 点击从13个示例中随机选择2个替换当前显示
   - 添加500ms节流防止频繁点击
   - 优化按钮交互动画效果

src/views/exampleShowcase.ts

@@ -4,7 +4,14 @@
 export function getExampleShowcaseContent(): string {
   return `
     <div class="example-showcase" id="exampleShowcase">
+      <div class="showcase-header">
         <div class="showcase-title">示例</div>
+        <button class="refresh-button" onclick="refreshExamples()" title="换一批">
+          <svg width="16" height="16" viewBox="0 0 24 24" fill="none" xmlns="http://www.w3.org/2000/svg">
+            <path d="M21.5 2V8M21.5 8H15.5M21.5 8L18 4.5C16.7429 3.24286 15.1767 2.35596 13.4606 1.93597C11.7446 1.51598 9.94736 1.57986 8.26381 2.12059C6.58027 2.66131 5.07831 3.65985 3.91872 4.99987C2.75913 6.33989 1.98648 7.96902 1.68 9.71M2.5 22V16M2.5 16H8.5M2.5 16L6 19.5C7.25714 20.7571 8.82331 21.644 10.5394 22.064C12.2554 22.484 14.0526 22.4201 15.7362 21.8794C17.4197 21.3387 18.9217 20.3401 20.0813 19.0001C21.2409 17.6601 22.0135 16.031 22.32 14.29" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round"/>
+          </svg>
+        </button>
+      </div>
       <div class="example-cards">
         <div class="example-card" onclick="sendExample(0)">
           <div class="example-icon">
@@ -62,12 +69,44 @@ export function getExampleShowcaseStyles(): string {
       display: none;
     }
 
+    .showcase-header {
+      display: flex;
+      align-items: center;
+      justify-content: space-between;
+      margin-bottom: 12px;
+    }
+
     .showcase-title {
       font-size: 14px;
       font-weight: 600;
       color: var(--vscode-foreground);
-      margin-bottom: 12px;
+    }
-      text-align: left;
+
+    .refresh-button {
+      background: transparent;
+      border: none;
+      color: var(--vscode-foreground);
+      cursor: pointer;
+      padding: 4px;
+      display: flex;
+      align-items: center;
+      justify-content: center;
+      border-radius: 4px;
+      transition: all 0.2s ease;
+      opacity: 0.6;
+    }
+
+    .refresh-button:hover {
+      opacity: 1;
+      background: var(--vscode-input-background);
+    }
+
+    .refresh-button svg {
+      transition: transform 0.3s ease;
+    }
+
+    .refresh-button:active svg {
+      transform: rotate(180deg);
     }
 
     .example-cards {
@@ -220,15 +259,74 @@ export function getExampleShowcaseStyles(): string {
  */
 export function getExampleShowcaseScript(): string {
   return `
-    // 示例文本数组
+    // 所有可用的示例
-    const exampleTexts = [
+    const allExamples = [
-      '生成一个SPI控制器',
+      '设计一个算术逻辑单元，完成常见运算',
-      '生成一个GMII接口的以太网UDP通信模块'
+      '实现一个优先编码器，多个输入同时有效时，只输出优先级最高的那个编号',
+      '实现一个译码器，把二进制编号转换成 one-hot 输出',
+      '实现一个移位寄存器，完成串行/并行数据移位与装载',
+      '实现一个按键消抖模块，解决机械按键抖动问题',
+      '实现一个跑马灯控制器，控制 LED 形成不同流动效果',
+      '实现一个序列检测器，检测串行输入中是否出现指定比特序列',
+      '实现一个LFSR 伪随机数发生器',
+      '实现一个自动售货机，模拟一个简单售货逻辑',
+      '实现一个交通灯控制器，控制两方向交通灯的切换',
+      '实现一个先进先出的数据缓冲区',
+      '单端口 RAM 读写控制器',
+      '实现一个移位加法乘法器，不用 * 运算符'
     ];
 
+    // 当前显示的示例文本
+    let exampleTexts = ['生成一个SPI控制器', '生成一个GMII接口的以太网UDP通信模块'];
+
     // 存储待发送的示例索引
     let pendingExampleIndex = -1;
 
+    // 节流控制
+    let refreshing = false;
+
+    // 刷新示例
+    function refreshExamples() {
+      if (refreshing) return;
+      refreshing = true;
+
+      const used = new Set();
+      const newExamples = [];
+      while (newExamples.length < 2) {
+        const idx = Math.floor(Math.random() * allExamples.length);
+        if (!used.has(idx)) {
+          used.add(idx);
+          newExamples.push(allExamples[idx]);
+        }
+      }
+      exampleTexts = newExamples;
+      updateExampleCards();
+
+      setTimeout(() => { refreshing = false; }, 500);
+    }
+
+    // 更新示例卡片显示
+    function updateExampleCards() {
+      const container = document.querySelector('.example-cards');
+      if (!container) return;
+      container.innerHTML = exampleTexts.map((text, i) => \`
+        <div class="example-card" onclick="sendExample(\${i})">
+          <div class="example-icon">
+            <svg width="24" height="24" viewBox="0 0 24 24" fill="none" xmlns="http://www.w3.org/2000/svg">
+              <path d="M14 2H6C5.46957 2 4.96086 2.21071 4.58579 2.58579C4.21071 2.96086 4 3.46957 4 4V20C4 20.5304 4.21071 21.0391 4.58579 21.4142C4.96086 21.7893 5.46957 22 6 22H18C18.5304 22 19.0391 21.7893 19.4142 21.4142C19.7893 21.0391 20 20.5304 20 20V8L14 2Z" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round"/>
+              <path d="M14 2V8H20" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round"/>
+              <path d="M16 13H8" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round"/>
+              <path d="M16 17H8" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round"/>
+              <path d="M10 9H9H8" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round"/>
+            </svg>
+          </div>
+          <div class="example-content">
+            <div class="example-title">\${text}</div>
+          </div>
+        </div>
+      \`).join('');
+    }
+
     // 直接发送示例消息
     function sendExample(index) {
       // 先检查邀请码验证状态