fork
Starts command and returns immediately, without waiting for it to finish.
Like await, the command runs inline — it is ticked by the enclosing CoroutineCommand and never reaches the Scheduler, so its requirements are not checked for conflicts. The enclosing command is not Command.done until every forked command has finished, and ending the enclosing command ends any that are still running.
To hand a command off to the Scheduler instead, call Command.schedule on it directly.