[ATR-19881] Improve navigation printing
Minor update to the logic in getRejectedDecisionNodes to support the offline retrieval of features of a chain which was rejected at the ComboHypo level.
Primary change for this MR hence in Trigger/TrigSteer/TrigCompositeUtils/Root/TrigCompositeUtilsRoot.cxx
Changes postponed as they have a large knock-on to feature finding (adding many false positives). Change at https://gitlab.cern.ch/tamartin/athena/-/blob/b23667af34fd5935d869fbaf7595d87de6926168/Trigger/TrigSteer/TrigCompositeUtils/Root/TrigCompositeUtilsRoot.cxx#L272 to be thought about some more first.
Now only - improve some debug printing.