Improvements to demo

[SaadBazaz]

• Perhaps host it on our GitHub pages instead of Vercel (as it's a static site, mostly)
• Use https://github.com/shadcn/ui for the UI
• (IF POSSIBLE) host it in the same repo
• Add links to:
  • NPM
  • GitHub
  • Discord
• Give it a nice hero, reminiscent of the original React Hook Form