Add support for tailwind v4

[slightlybelowzen]

It would be super helpful if we could add support for tailwind v4, there's a bunch of new features and in general better DX which would be nice to have!
I'm happy to poke around the code and try and work on it myself if (I understand it's probably not a super high priority issue)!

[hayleigh-dot-dev]

This would be a great thing to support. My intention for Lustre's dev-tools is for it to be a largely on-rails experience (for folks with more configuration needs etc I recommend they use vite) so I think there's probably some thinking to be done around how this will work 🤔

Should we support both versions, or just v4? Supporting just v4 I suppose would be a major release of the library because it'd break existing users' setups? I've not dug super hard into v4 so I'm not sure what all the implications are. What are you thoughts?

[slightlybelowzen]

Got it, that makes sense.

Yeah absolutely, it should be a choice especially since by default v4 removes the tailwind.config.js file and allows people to define themes through css directives @theme, which would be a pretty breaking change.

Also, while I was initially poking around the codebase to see how tailwind support works I realised tailwind@v4 doesn't have releases for all the platforms that 3.4.1 has defined (I might be wrong, not a 100% sure about this one).

I'll try and do some digging this weekend to see if I can come up with a draft.