Track perks unlocked per grant and remove only those on race loss instead
of restoring a full pre-apply snapshot; re-run ReevaluateAfterLevelUp at
post-rollback levels so a concurrent winner's path-auto unlocks survive.
Capture pre-skill-apply XP and perk snapshots; on TryRecord loss reverse
each applied skill row via negative delta and restore the perk snapshot so
level-up unlocks from the loser call are reverted without clobbering a
concurrent winner's XP.
VinPropane