Feature: `webi info|versrions <installer>`, `webi discord-invite`

- [ ] `webi info <installer>` should show (and possibly open) the URL with the cheat sheet.
- [ ] `webi versions <installer>` should show the relevant `https://webinstall.dev/api/releases/<installer>.tab` `?os=macos&arch=aarch64&pretty=true`
- [ ] `webi discord-invite` to join the discord
- [ ] `webi twitter-follow` to follow on twitter