Enable/disable services

[gsalinas]

Some 402 drivers (at a minimum, the one I'm using) support designating one of their outputs as a dedicated brake output, set automatically by the 402 state machine, for use with motors with brakes.

This PR adds enable and disable services so that you can move your drive from Operational state to Switched On Disabled state; for situations where a user wants the brake engaged whenever stationary, this gives the necessary hooks to do so - verify that your motion is finished according to your situation, then call the disable service, and call enable before moving again.

Additionally, the enable service allows you to get back into an operational state without calling init, which always redoes homing even if the drive had already been homed.

Thank you!

[hellantos]

@gsalinas
Looks great. We had taken the cia402 implementation from the ROS1 stack where the init recover and halt functions were the main interactions. I personally would be in favor of having more fine grained control with dedicated services as you proposed. In this case I would propose to as well add a home service.

[ipa-vsp]

@gsalinas could you please fix the pre-commit