feat: 新增CWD评论系统前后端代码及文档

refactor: 移除旧版评论系统代码并重构为Vue3前端

docs: 更新后端配置文档说明

fix: 修复评论提交频率限制和邮件通知逻辑

style: 格式化代码并优化样式

test: 添加Vitest测试配置

build: 更新依赖项和构建配置

chore: 清理无用文件和缓存

cwd-comments-api/src/utils/email.ts

@@ -0,0 +1,98 @@
+import { Bindings } from '../bindings';
+
+/**
+ * 回复通知邮件
+ */
+export async function sendCommentReplyNotification(
+  env: Bindings,
+  params: {
+    toEmail: string;
+    toName: string;
+    postTitle: string;
+    parentComment: string;
+    replyAuthor: string;
+    replyContent: string;
+    postUrl: string;
+  }
+) {
+  const { toEmail, toName, postTitle, parentComment, replyAuthor, replyContent, postUrl } = params;
+
+  const html = `
+      <div style="font-family: sans-serif; line-height: 1.6; color: #333;">
+        <p>Hi <b>${toName}</b>，</p>
+        <p>${replyAuthor} 回复了你在 <b>${postTitle}</b> 中的评论：</p>
+        <blockquote style="margin: 10px 0; padding: 10px; border-left: 4px solid #e2e8f0; background: #f8fafc;">
+          ${parentComment}
+        </blockquote>
+        <p>最新回复：</p>
+        <blockquote style="margin: 10px 0; padding: 10px; border-left: 4px solid #3b82f6; background: #eff6ff;">
+          ${replyContent}
+        </blockquote>
+        <p style="margin-top: 20px;">
+          <a href="${postUrl}" style="background: #3b82f6; color: white; padding: 10px 20px; text-decoration: none; border-radius: 6px; display: inline-block;">
+            查看完整回复
+          </a>
+        </p>
+        <hr style="border: none; border-top: 1px solid #eee; margin-top: 30px;">
+        <p style="font-size: 12px; color: #999;">此邮件由系统自动发送，请勿直接回复。</p>
+      </div>
+    `;
+
+  if (!env.SEND_EMAIL || !env.CF_FROM_EMAIL) {
+    throw new Error('未配置邮件发送绑定或发件人地址');
+  }
+
+  await env.SEND_EMAIL.send({
+    to: [{ email: toEmail }],
+    from: { email: env.CF_FROM_EMAIL },
+    subject: `你在 example.com 上的评论有了新回复`,
+    html
+  });
+}
+
+/**
+ * 站长通知邮件
+ */
+export async function sendCommentNotification(
+  env: Bindings,
+  params: {
+    postTitle: string;
+    postUrl: string;
+    commentAuthor: string;
+    commentContent: string;
+  }
+) {
+  const { postTitle, postUrl, commentAuthor, commentContent } = params;
+  const toEmail = await getAdminNotifyEmail(env);
+
+  const html = `
+    <div style="font-family: sans-serif;">
+      <p><b>${commentAuthor}</b> 在文章《${postTitle}》下发表了评论：</p>
+      <div style="padding: 15px; border: 1px solid #ddd; border-radius: 8px;">
+        ${commentContent}
+      </div>
+      <p><a href="${postUrl}">点击跳转到文章</a></p>
+    </div>
+  `;
+
+  if (!env.SEND_EMAIL || !env.CF_FROM_EMAIL) {
+    throw new Error('未配置邮件发送绑定或发件人地址');
+  }
+
+  await env.SEND_EMAIL.send({
+    to: [{ email: toEmail }],
+    from: { email: env.CF_FROM_EMAIL },
+    subject: `新评论通知：${postTitle}`,
+    html
+  });
+}
+
+// 读取管理员通知邮箱：优先 KV 设置，其次环境变量
+async function getAdminNotifyEmail(env: Bindings): Promise<string> {
+  if (env.CWD_CONFIG_KV) {
+    const val = await env.CWD_CONFIG_KV.get('settings:admin_notify_email');
+    if (val) return val;
+  }
+  if (env.EMAIL_ADDRESS) return env.EMAIL_ADDRESS;
+  throw new Error('未配置管理员通知邮箱');
+}