引入 mdx 以显示 markdown 文档，使用 tailwind 默认排版样式；修正 eslint 规则

next.config.ts

@@ -1,7 +1,18 @@
 import type { NextConfig } from "next"
+import createMDX from "@next/mdx"
+import remarkGfm from 'remark-gfm'
 
 const nextConfig: NextConfig = {
   output: "standalone",
+  pageExtensions: ['js', 'jsx', 'md', 'mdx', 'ts', 'tsx'],
 }
 
-export default nextConfig
+const withMdx = createMDX({
+  extension: /\.(md|mdx)$/,
+  options: {
+    remarkPlugins: [remarkGfm],
+    rehypePlugins: [],
+  }
+})
+
+export default withMdx(nextConfig)