perf: 懒加载和动态加载优化

src/pages/index.tsx

@@ -1,12 +1,9 @@
-import React, { useEffect } from 'react';
-import { useRouter } from 'next/router';
-import { Card, Text, Box, Heading, Flex } from '@chakra-ui/react';
+import React from 'react';
+import { Card } from '@chakra-ui/react';
 import Markdown from '@/components/Markdown';
 import { introPage } from '@/constants/common';
 
 const Home = () => {
-  const router = useRouter();
-
   return (
     <Card p={5} lineHeight={2}>
       <Markdown source={introPage} isChatting={false} />