Raise an error when an unknown/unsupported G/M command is requires.

This will address #10546

- Add an option to retry G29, optionally executing a G-code procedure after each failed probe.

* Automatically reset stepper timeout in manage_inactivity

Any code that adds moves to the planner can skip resetting the stepper timeout. We can let `idle` / `manage_inactivity` reset the timer whenever it detects any moves in the planner.

* blocks_queued => has_blocks_queued

Followup to d6df032

Addressing #7707