refactor: migrate to rsc and app dir

app/about/About.tsx

@@ -0,0 +1,16 @@
+'use client'
+
+import { MDXLayoutRenderer } from 'pliny/mdx-components'
+import { MDXComponents } from '@/components/MDXComponents'
+
+const DEFAULT_LAYOUT = 'AuthorLayout'
+
+export default function About({ author }) {
+  return (
+    <MDXLayoutRenderer
+      layout={author.layout || DEFAULT_LAYOUT}
+      content={author}
+      MDXComponents={MDXComponents}
+    />
+  )
+}

app/about/page.tsx

@@ -0,0 +1,7 @@
+import { allAuthors } from 'contentlayer/generated'
+import About from './About'
+
+export default function Page() {
+  const author = allAuthors.find((p) => p.slug === 'default')
+  return <About author={author} />
+}