feat: add a TUI interface to rust-peer

[dhuseby]

This PR re-organizes the rust-peer significantly and adds a TUI interface to it that is very similar to the go-peer TUI interface. This has been tested against the go-peer and it works. I also tested it on Linux and Macos.

Key bindings:

• [tab]: switches between chat UI and log UI
• ctrl-c: shuts down the peer
• ctrl-p: gathers the known gossipsub peers and their subscribed topics and dumps them to the system messages
• [enter]: send the typed in chat message (only on the chat UI)

Here's a short demo video I recorded

[dhuseby]

@jxs @elenaf9 I'm ready to land this peer. It's blocking me getting the universal connectivity workshop completed. If there's no objections, I'll land this on the 23rd.