Description

There are a couple of refactoring that fall out of #98874. This issue captures what still has to be done:

• Computing the amount of required memory externally and passing it to AssignmentPlan.accountMemory() is cumbersome. It can be done internally in the class.
• This would simplify the functions
  • ZoneAwareAssignmentPlanner.swapOriginalModelsInPlan
  • AbstractPreserveAllocations.mergePreservedAllocations
  • TrainedModelAssignmentRebalancer.copyAssignments