feat: 支持用户删除自己的评论

- CommentItem: 添加删除按钮（仅显示在自己的评论上）
- CommentItem: 添加删除确认对话框，防止误删
- CommentList: 传递 currentUserId 和 onDelete 到 CommentItem
- EventCommentSection: 添加 handleDeleteComment 处理函数
- mock handler: 使用真实登录用户信息创建评论

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

src/mocks/handlers/event.js

@@ -5,6 +5,7 @@ import { http, HttpResponse } from 'msw';
 import { getEventRelatedStocks, generateMockEvents, generateHotEvents, generatePopularKeywords, generateDynamicNewsEvents } from '../data/events';
 import { getMockFutureEvents, getMockEventCountsForMonth, toggleEventFollowStatus, isEventFollowed } from '../data/account';
 import { generatePopularConcepts } from './concept';
+import { getCurrentUser } from '../data/users';
 
 // 模拟网络延迟
 const delay = (ms = 300) => new Promise(resolve => setTimeout(resolve, ms));
@@ -1498,15 +1499,19 @@ export const eventHandlers = [
         console.log('[Mock] 发表评论, eventId:', eventId, 'content:', body.content);
 
         try {
+            // 获取当前登录用户信息
+            const currentUser = getCurrentUser();
+
             // 模拟创建新评论
             const newComment = {
                 id: `comment_${eventId}_${Date.now()}`,
                 content: body.content,
                 content_type: body.content_type || 'text',
                 author: {
-                    id: 'current_user',
-                    username: '当前用户',
-                    avatar: null,
+                    id: currentUser?.id || 'current_user',
+                    // 与导航区保持一致：优先显示昵称
+                    username: currentUser?.nickname || currentUser?.username || currentUser?.email || '当前用户',
+                    avatar: currentUser?.avatar_url || null,
                 },
                 created_at: new Date().toISOString(),
                 likes_count: 0,