Bind to ports instead of urls

[Mirko-von-Leipzig]

Replace server binding URLs configs with ports instead. This is much simpler from a usability perspective. Unfortunately this doesn't eliminate URLs from all configs since these are still required to connect components, but at least this covers the base use case.

0xMiden/faucet#156 (review)

Also, I wonder if we should adapt the same methodology for specifying server binding addresses in the node (cc @Mirko-von-Leipzig).

I think its a good idea; the only downside is that it means they're always hosted on the public network interface i.e. 0.0.0.0: vs localhost:. But random ports shouldn't be exposed on the firewall/router so its probably still a safe default for users.

[sergerad]

I will tend to this once the bundled command is removed (#1786 is merged)