fix(docs): wrap adjacent JSX elements in fragments for Prettier compat

[pierluigilenoci]

Summary

Fixes 4 Astro files that caused Prettier's Astro parser to fail with SyntaxError: Adjacent JSX elements must be wrapped in an enclosing tag.

Changes

File	Fix
site/src/components/head/Head.astro	Wrap <Stylesheet> + <ScssProd.default> in <>...</>
site/src/layouts/DocsLayout.astro	Wrap <button> + <strong> + <hr> + <div> in <>...</>
site/src/components/shortcodes/Code.astro	Replace empty fragment (<></>) with null
site/src/components/head/ScssProd.astro	Reformatted only (no logic change)

Motivation

These files contain adjacent JSX elements inside conditional expressions without a wrapping fragment, which is invalid JSX and causes prettier-plugin-astro to error out. After this fix, prettier --check site passes on all Astro files.

Test plan

• npx prettier --plugin prettier-plugin-astro -c <4 files> — passes
• No functional changes — only JSX structure and formatting

[pierluigilenoci]

cc @julien-deramond @mdo @louismaximepiton — these are the 4 Astro files that fail prettier --check due to adjacent JSX elements not wrapped in fragments. Minimal fix, no logic changes.

[julien-deramond]

Thanks to your PR, I spotted that we haven't enabled prettier-plugin-astro in our Prettier config 🙃

I've made the changes in #42390. Maybe this PR, when rebased, can be closed as npm run docs-prettier-check doesn't raise any errors.

I'm not sure why you add to modify other files in this PR. Is there an issue in our conf?

[pierluigilenoci]

Thanks @julien-deramond — you're right, enabling prettier-plugin-astro in #42390 was the proper fix. After rebasing, the formatting issues are gone without needing the fragment wrappers. Closing this as superseded. Appreciate the quick turnaround!