Proposal to add extensions.json

[Jacksondr5]

I started working on #169 and noticed that my editor was running Prettier as the default formatter on save, causing a lot of noisy changes. After looking in the .vscode/settings.json, I noticed that the default formatter was set to "biomejs.biome", which I think references the Biome extension. Problem is that I don't have this extension, so my editor is defaulting back to Prettier.

Would y'all be open to adding a .vscode/extensions.json to prompt contributers to install the extensions that are already configured in settings.json? Based on what I can gather from the settings.json, I think the extensions.json would be something like this:

{
  "recommendations": ["biomejs.biome", "bradlc.vscode-tailwindcss", "unifiedjs.vscode-mdx"]
}

Not 100% sure about the mdx one, there are several options and I'm not sure which one "mdx.experimentalLanguageServer": true is referring to in the settings.

Happy to offer a PR for it.

[juliusmarminge]

sure