`fly proxy` doesn't forward UDP ports

[anatoli_devops]

@mayailurus

(And also, I use that feature of SSH and spiped a lot, myself, for forwarding various kinds of stream-style communication. It was neat to see it in flyctl, too!)

There are other mechanisms that can tunnel UDP across streaming protocols, but they come with caveats, so they’re best avoided whenever it’s possible to do so.

So it should be possible to use netcat to listen for UDP traffic and forward it through local socket to remote server (with Tarsnap - The spiped secure pipe daemon ) where reverse netcat is running. What are the caveats here?