breaking: Layout element and style improvements

[shuding]

With the docs theme, it's now required to have this layout function:

export default function MyApp({ Component, pageProps }) {
  // Use the layout defined at the page level, if available
  const getLayout = Component.getLayout || ((page) => page);

  return getLayout(<Component {...pageProps} />);
}

[vercel]

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nextra – ./

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nextra-theme-docs-dev – ./examples/swr-site

🔍 Inspect: https://vercel.com/vercel/nextra-theme-docs-dev/GFtMa6Rga48Vs2bVCZW1fvRXF7Ew
✅ Preview: https://nextra-theme-docs-dev-git-shu-d2f7.vercel.sh