Deprecate Repository And Add Notice

[ScottAwesome]

It is apparent that windicss is no longer under active maintenance, given this, written by @antfu

While Windi CSS is no longer actively maintained (as of March 2023), you may consider UnoCSS as a "spiritual successor" of Windi CSS.

see here

I think it would then, be appropriate to archive this repository, or at least give a deprecation notice. Same with the npm packages

[alexanderniebuhr]

#904