feat(remix-dev/vite): support HMR for MDX

[hi-ogawa]

Closes: #7788

I went over some relevant discussions and other implementations regarding HMR-ing MDX:

• Need a way to transform other plugin(such as mdx)'s output. vitejs/vite-plugin-react#38
• https://github.com/cyco130/vite-plugin-mdx/blob/main/packages/vite-plugin-mdx/src/index.ts#L84
• https://github.com/mdx-js/mdx/blob/main/packages/rollup/lib/index.js

and my conclusion is that HMR should just work as long as MDX files goes through "react-refresh/babel" transform.
Currently remix-react-refresh-babel already enforce: "post" and @mdx-js/rollup has no enforce, so simply tweaking regex filter to allow .mdx seems to be enough.

However, as it's already mentioned, mdx uses export for local variable and also for frontmatter plugin, so this unfortunately forces full-reload when mdx includes frontmatter, but I think this might be okay for starter.
Please let me know if it's desired to improve more HMR feature for MDX (for example, maybe extend HMR acceptExports trick to cover frontmatter in some way? or improve "Could not Fast Refresh" message for frontmatter?).
Thanks!

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• Docs
• Tests

Testing Strategy:

[changeset-bot]

🦋 Changeset detected

Latest commit: 39ee9cd

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 16 packages

Name	Type
@remix-run/dev	Patch
create-remix	Patch
remix	Patch
@remix-run/architect	Patch
@remix-run/cloudflare	Patch
@remix-run/cloudflare-pages	Patch
@remix-run/cloudflare-workers	Patch
@remix-run/css-bundle	Patch
@remix-run/deno	Patch
@remix-run/eslint-config	Patch
@remix-run/express	Patch
@remix-run/node	Patch
@remix-run/react	Patch
@remix-run/serve	Patch
@remix-run/server-runtime	Patch
@remix-run/testing	Patch

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[pcattori]

Superceded by #8711

Thanks again for looking into this issue! Added you as a co-author on the other PR since our testing setup has changed since this PR was opened.