Draft: add PrUPTracks

should be merged with Rec!4288

added Upgrade2 label

assigned to @mingjie

mentioned in merge request Rec!4288

Hi @mingjie : we try to remove LHCb/run5 in favour of having all pr classes a part just of rec; to minimise the work maintaining the branches and avoid destructive interference with activities for the current data-taking period. it looks like this code can mostly be moved to Rec/PrEvent rather than being kept here. Can you see if this works?

No problem! I will move it to Rec

Great! many thanks