使用cookie管理会话主题，并修复深色主题初始化的BUG

pages/_app.js

@@ -17,7 +17,7 @@ import { ThemeProvider } from '@/lib/theme'
 const Ackee = dynamic(() => import('@/components/Ackee'), { ssr: false })
 const Gtag = dynamic(() => import('@/components/Gtag'), { ssr: false })
 
-function MyApp ({ Component, pageProps }) {
+const MyApp = ({ Component, pageProps }) => {
   return (
     <LocaleProvider>
       <ThemeProvider>

pages/index.js

@@ -25,7 +25,7 @@ export async function getStaticProps () {
   }
 }
 
-const index = ({ posts, tags, meta }) => {
+const Index = ({ posts, tags, meta }) => {
   return (
     <BaseLayout meta={meta} tags={tags}>
       <div className='flex-grow'>
@@ -36,4 +36,4 @@ const index = ({ posts, tags, meta }) => {
   )
 }
 
-export default index
+export default Index