feat: add vitepress

[dario-piotrowicz]

This PR adds VitePress detection.

This PR is a recreation of #6630 from @TheAlexLichter since that PR got quite stale for a while (I hope you don't mind Alex 😄🙏)

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[serhalp]

Thank you, Dario! Looks great overall — just a bit of a conundrum around what settings to populate 🤔.

[serhalp]

🤔 Hmm, VitePress is an interesting case because of https://vitepress.dev/guide/routing#root-and-source-directory. It's doubly strange because the "project root" isn't even configurable; it's an ephemeral concept specified on the command line 🙃.

vitepress build foo emits build output into ./foo/.vitepress/dist. VitePress calls ./foo here the "project root". If you run vitepress build without a root arg, root is set to pwd, so the output ends up in ./vitepress/dist. This isn't entirely a build output concern—the project root is where the VitePress config file is expected, etc. so it needs to be correct.

🤔🤔🤔

I don't think it's possible to make this perfect. Perhaps the best we can do is use their current recommended config, which is compatible with the defaults emitted by npx vitepress init (i.e. project root = ./docs).

Suggested change

	command: 'vitepress build',
	directory: '.vitepress/dist',
	command: 'vitepress build docs', // ideally we don't use `npm run build:docs` here due to pnpm, etc.
	directory: 'docs/.vitepress/dist',

What do you think? We could do some hacky things inspecting the user build command, but I'm not sure that's worth the complexity...

[serhalp]

See discussion below. If we want this to align with the defaults from npx vitepress init, we should use:

Suggested change

	command: 'vitepress dev',
	command: 'vitepress dev docs',

[serhalp]

Let's add vitepress to the big list of excluded dependencies for vite: https://github.com/dario-piotrowicz/netlify-build/blob/796ebb173d716151fe0e864c724be1e67c1cdd1c/packages/build-info/src/frameworks/vite.ts#L7

Huh, never mind, vitepress projects don't have a direct dependency on vite!