Cyber limbs fixes [BUGFIXES] [RUNTIME FIX]

- Fixes the damage_converter.dm symptom trying to heal robotic limbs
- Adds some NEEDED sanity checks to attempt_initiate_surgery (certain human only procs were being called on monkeys/other mobs)


Edit: ( Apparently I'm also removing some file directories someone defined, I thought we weren't supposed to define those anyways?)