run method
Implementation
@override
FutureOr<String?> run(ParsedInputs inputs, List<String> args) {
final path = defaultSubCommandPath;
if (path != null) return runChildCommand(path, inputs, args);
// Nothing was selected below this group, so the invocation is a question
// about the children it owns. Rendering the resolved registry is the
// answer, and it is the group's own rather than the executor's.
return help?.format();
}