TCP server decentralization - picking random TCP servers

[serialrf433]

The application https://github.com/thatSFguy/reticulum-mobile-app have a functionality to prevent TCP server centralization.

Default TCP transport node is picked at random from a curated rotation of community-run rnsd servers

Written in here: https://github.com/thatSFguy/reticulum-mobile-app/blob/master/FDROID_RFP.md

Such functionality combined with a bigger TCP server list in Columba #690 would be something nice to have build in.