Run an inlets PRO tunnel server for free on fly.io

One of the earliest things the community did with inlets was to run a tunnel server on Heroku, but their free tier left a lot to be desired.

Fly's new PaaS gets you up to 3x tunnels hosted for free. It might be useful if you use inlets or some other server software that runs in containers.

You can also connect this to Kubernetes for Ingress.