2111 - Dont report same collision pair multiple times

Observation: If the pair exists in the previous slice, we don’t need to add anything. Any collision would have been handled in the previous slice. If it doesn’t exist in the previous slice, the only other possible place is the next slice, which will be handled by this same rule. There are no non-contiguous same-pairs stored. Create double buffered bit vector on the stack to track previous and next a and b instances processed. On both a and b bits set on previous, do not re-store event. Cheap and easy. Add an additional debug view of collision_damage.