Improve core server command line experience.

Add more advanced command line output, such as RAM+CPU usage, registered subsystems, communication data, debugging, etc. Should also provide a runtime input system; while running, core should process input via a list of commands (modularize minparse a bit?).

Begin by locating the core server command-line handling and the minparse code mentioned in the issue. Clarify the required output, runtime input commands, registered subsystem reporting, resource metrics, communication data, and debugging scope before implementation; done means the agreed command set and output are available while the server runs.

Written by the indexing model from the issue text.