[Feature] Tailwind CSS V4 Support

[uncomplexity]

unsure if this can break anything yet

• https://tailwindcss.com/blog/tailwindcss-v4-beta

[colinaaa]

This plugin could not be used directly with Tailwind CSS V4 since the PostCSS plugin is renamed from tailwindcss to @tailwindcss/postcss, which will break this plugin since we are using import('tailwdincss') with PostCSS now.

But we will certainly support Tailwind CSS V4, not with PostCSS but with the new Oxide engine(just like Vite does).

[colinaaa]

For those who are interested in Tailwind CSS V4 support:

I made a prototype implementation on the v4 branch.

• For Rspack, it would panic(see [Bug]: panic when using compilation.rebuildModule with CssExtractRspackPlugin web-infra-dev/rspack#9058)
• For webpack, it does not output the correct CSS(I think it is a bug of mini-css-extract-plugin).

We will try to fix these problems in the next few week.

Stay tuned!