Use command description to fill Candidate in console

[gnodet]

It would be nice if the console registry would provide completer that can leverage the command descriptions, this would allow displaying completion list for commands like the following:

I think the command description could be retrieved using commandRegistry.commandInfo(name), however, the command names completer is built here and I don't see any easy way to access the command registry.

In addition, it would be nice if the Picocli registries would be somehow compatible with the needed change.

@mattirn any idea ?