Prepare for Tailwind 4.0

[100phlecs]

We can explore using a rust NIF to load in the classes on mix format, eliminating the generation step as well as the js loader script

If the above works, then that greatly simplifies getting custom classes, almost for free

[100phlecs]

It looks like the rust part only covers parsing. All of the class resolution/ordering/outputting CSS seems to still happen in JS unless I'm mistaken.

In addition, it looks accessing the theme isn't going to be supported in 4.0, or a new API has to be uncovered

It may be more productive to reverse engineer the sort order instead