Add hCaptcha to sign up form

[oskarrough]

Low priority for now, but would be good to add to avoid spam like we had/have on Firebase.

• https://supabase.com/docs/guides/auth/auth-captcha
• https://docs.hcaptcha.com/#add-the-hcaptcha-widget-to-your-webpage

I created a hCaptcha account with our protonmail for laters.

[4www]

Sure thing! Though in the case of our spam, not sure it'll change anything... i think the people "spaming" with all the small businesses page, are doing it by hand...

[oskarrough]

Whether it prevents spam is a different discussion, but hcaptcha is at least now supported and live.