Request: Support redirect at the proxy level

[guillaumebriday]

It would be great if Kamal-proxy could manage redirects at the proxy level.

A key example would be redirecting non-www to www, or the other way around.

Here's how we handled it with Traefik: https://lesscodeworks.com/redirect-from-www-to-non-www-with-kamal-and-traefik
And here's an example for doing it with Rails: https://masilotti.com/rails-redirect-www/

What do you think about it? How do you handle it at basecamp?