[idea] use Shinylive in pkg docs

This is an idea that I would let you refine it better.

I would love to see the documentation (README, vignettes, function reference, etc.) more _interactive_ using Shinylive.

Recently we created a small tool for that purpose `roxy.shinylive`. Feel free to use it. It's already in the modules packages and I think it's robust enough to be implemented in the _core_ packages.