Fold cache not used when loading design starting from design browser #886
Description
When we construct a new PoseEditMode with an initSolution, we surgically pull data instead of using showSolution, so we skip over the fold cache loading. setPuzzle is very sensitive to doing things in the right order for initializing data structures, so if we want to delegate to showSolution (which I think we should) we'll have to investigate carefully. NB this may also avoid some of the schenanigans we currently go through to load the fold cache to set the target structure