Fixes cyborg latejoining, allows mid-round joining

Basically, this is #7002 without the runtimes and being left at the BS12 title screen.

The problem is that the job controller was `Robotize()`ing the new cyborg, then `AttemptLateSpawn()` tried to a) read from the now-deleted pre-robotization mob, and b) `Robotize()` again.