feat: 实现 Redux 全局状态管理事件关注功能

本次提交实现了滚动列表和事件详情的关注按钮状态同步：

✅ Redux 状态管理
- communityDataSlice.js: 添加 eventFollowStatus state
- 新增 toggleEventFollow AsyncThunk（复用 EventList.js 逻辑）
- 新增 setEventFollowStatus reducer 和 selectEventFollowStatus selector

✅ 组件集成
- DynamicNewsCard.js: 从 Redux 读取关注状态并传递给子组件
- EventScrollList.js: 接收并传递关注状态给事件卡片
- DynamicNewsDetailPanel.js: 移除本地 state，使用 Redux 状态

✅ Mock API 支持
- event.js: 添加 POST /api/events/:eventId/follow 处理器
- 返回 { is_following, follower_count } 模拟数据

✅ Bug 修复
- EventDetail/index.js: 添加 useRef 导入
- concept.js: 导出 generatePopularConcepts 函数
- event.js: 添加 /api/events/:eventId/concepts 处理器

功能：
- 点击滚动列表的关注按钮，详情面板的关注状态自动同步
- 点击详情面板的关注按钮，滚动列表的关注状态自动同步
- 关注人数实时更新
- 状态在整个应用中保持一致

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

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

src/views/Community/components/DynamicNewsDetail/DynamicNewsDetailPanel.js

@@ -2,6 +2,7 @@
 // 动态新闻详情面板主组件（组装所有子组件）
 
 import React, { useState, useCallback } from 'react';
+import { useDispatch, useSelector } from 'react-redux';
 import {
   Card,
   CardBody,
@@ -15,6 +16,7 @@ import {
 import { getImportanceConfig } from '../../../../constants/importanceLevels';
 import { eventService } from '../../../../services/eventService';
 import { useEventStocks } from '../StockDetailPanel/hooks/useEventStocks';
+import { toggleEventFollow, selectEventFollowStatus } from '../../../../store/slices/communityDataSlice';
 import EventHeaderInfo from './EventHeaderInfo';
 import EventDescriptionSection from './EventDescriptionSection';
 import RelatedConceptsSection from './RelatedConceptsSection';
@@ -29,11 +31,17 @@ import TransmissionChainAnalysis from '../../../EventDetail/components/Transmiss
  * @param {Object} props.event - 事件对象（包含详情数据）
  */
 const DynamicNewsDetailPanel = ({ event }) => {
+  const dispatch = useDispatch();
   const cardBg = useColorModeValue('white', 'gray.800');
   const borderColor = useColorModeValue('gray.200', 'gray.700');
   const textColor = useColorModeValue('gray.600', 'gray.400');
   const toast = useToast();
 
+  // 从 Redux 读取关注状态
+  const eventFollowStatus = useSelector(selectEventFollowStatus);
+  const isFollowing = event?.id ? (eventFollowStatus[event.id]?.isFollowing || false) : false;
+  const followerCount = event?.id ? (eventFollowStatus[event.id]?.followerCount || event.follower_count || 0) : 0;
+
   // 使用 Hook 获取实时数据
   const {
     stocks,
@@ -49,10 +57,6 @@ const DynamicNewsDetailPanel = ({ event }) => {
   const [isHistoricalOpen, setIsHistoricalOpen] = useState(true);
   const [isTransmissionOpen, setIsTransmissionOpen] = useState(false);
 
-  // 关注状态管理
-  const [isFollowing, setIsFollowing] = useState(false);
-  const [followerCount, setFollowerCount] = useState(0);
-
   // 自选股管理（使用 localStorage）
   const [watchlistSet, setWatchlistSet] = useState(() => {
     try {
@@ -64,23 +68,10 @@ const DynamicNewsDetailPanel = ({ event }) => {
   });
 
   // 切换关注状态
-  const handleToggleFollow = async () => {
-    try {
-      if (isFollowing) {
-        // 取消关注
-        await eventService.unfollowEvent(event.id);
-        setIsFollowing(false);
-        setFollowerCount(prev => Math.max(0, prev - 1));
-      } else {
-        // 添加关注
-        await eventService.followEvent(event.id);
-        setIsFollowing(true);
-        setFollowerCount(prev => prev + 1);
-      }
-    } catch (error) {
-      console.error('切换关注状态失败:', error);
-    }
-  };
+  const handleToggleFollow = useCallback(async () => {
+    if (!event?.id) return;
+    dispatch(toggleEventFollow(event.id));
+  }, [dispatch, event?.id]);
 
   // 切换自选股
   const handleWatchlistToggle = useCallback(async (stockCode, isInWatchlist) => {