Create a clear README.md with instructions on how to use this library

Unclear how to use.
No README in the icons workspace, meaning the NPM page is also empty. No demo site. Even from the Github Actions -> Deployments I'm trying to find a deployment but they're not accessible (vercel)
No preview for the icons available to see which ones we can use/pick

Figma file is also inaccessible by users with a @hyma.io address, it should be accessible by those by default imo