Cherry pick ftag ghost labels
This cherry picks !33501 (merged) and !33746 (merged), which add ghost-association based labels to VR jets. These aren't scheduled yet in master, so this is just porting C++ code.
This cherry picks !33501 (merged) and !33746 (merged), which add ghost-association based labels to VR jets. These aren't scheduled yet in master, so this is just porting C++ code.