Export the `tailwind-merge` validators

While writing a complex tailwind styles that may conflict with existing styles sometimes requires `classGroups` with validators. I often use the validators from the original `tailwind-merge`. Yes I can or write a custom validator, (or copy-paste the code 👈) but using it from the library itself would be easier.

Start by tracing how classGroups and validators are currently handled in the TypeScript source, then compare the public API with the validators provided by tailwind-merge. The work is done when consumers can import the existing validators from cnfast and use them in classGroups without copying or reimplementing them.

Scritto dal modello di indicizzazione a partire dal testo della issue.