feat: Show chat tab infiniflow#2247 (infiniflow#2307)

### What problem does this PR solve?

feat: Show chat tab infiniflow#2247
### Type of change


- [x] New Feature (non-breaking change which adds functionality)

web/src/layouts/components/header/index.tsx

@@ -9,7 +9,7 @@ import { useLocation } from 'umi';
 import Toolbar from '../right-toolbar';
 
 import { useFetchAppConf } from '@/hooks/logic-hooks';
-import { SearchOutlined } from '@ant-design/icons';
+import { MessageOutlined } from '@ant-design/icons';
 import styles from './index.less';
 
 const { Header } = Layout;
@@ -26,8 +26,8 @@ const RagHeader = () => {
   const tagsData = useMemo(
     () => [
       { path: '/knowledge', name: t('knowledgeBase'), icon: KnowledgeBaseIcon },
-      // { path: '/chat', name: t('chat'), icon: MessageOutlined },
-      { path: '/search', name: t('search'), icon: SearchOutlined },
+      { path: '/chat', name: t('chat'), icon: MessageOutlined },
+      // { path: '/search', name: t('search'), icon: SearchOutlined },
       { path: '/flow', name: t('flow'), icon: GraphIcon },
       { path: '/file', name: t('fileManager'), icon: FileIcon },
     ],