With the uptick of mmus, and other add-on hardware to klipper machines, it would be great to have the option of making a MCU optional. For example:
[MCU AFC]
Uuid: blah3849blah
Optional: ( True | False ) # default would be False
Functionally, when klipper starts and checks MCU status, if optional is False, everything works as it is now.
If optional is set to true and the MCU exists at startup, everything is as it is now.
If optional is set to true and the MCU does not exist at startup, klipper then completely ignores this MCU.
In this setup, if I unplug my mmu (or other device whether it be can or USB), I would not have to make config changes each time I plug or unplug a unit. And by making it a optional flagg of the mmu tag defaulting to False, current users would not have to make any changes to their configs.