chore: update Supabase examples.

[thorwebdev]

Removing the outdated example and replacing it with a list of useful Next.js + Supabase examples and resources. Does that work for y'all?

Documentation / Examples

• Make sure the linting passes by running pnpm build && pnpm lint
• The "examples guidelines" are followed from our contributing doc

[leerob]

Unfortunately, this would block folks wanting to do create-next-app -e with-supabase type cloning, for example. I would recommend instead keeping an example up to date here 🙏 In the future, we will be removing some of the empty directory README only "examples".

[thorwebdev]

That's a good point, thanks @leerob

I've removed the old with-supabase-auth-realtime-db example and replaced it with an up to date with-supabase example. PTAL

Let me know if you're okay with the name change or if you'd prefer to stick with with-supabase-auth-realtime-db? E.g. would it affect this listing: https://vercel.com/templates/next.js/supabase-authentication ?

[balazsorban44]

Closing in favor of #51335