Redo function

[Terriuss]

Added full Undo/Redo support for map size/playable area changes and for moving multiple elements at once.

Changes:

Map size Undo/Redo

New MapTemplate.RestoreMapSizeConfig(int, Rect2) restores both map size and playable area.

MapView now saves the old values when resizing starts and adds a single MapPropertiesStackEntry on commit.

Added an UndoRedoStack.IsProcessing check to avoid recording changes during an active Undo/Redo.

Group transforms

Fixed GroupStackEntry so Undo goes backwards and Redo goes forwards, keeping things consistent.

Added SuppressIndividualTransformStacking to stop cluttering the stack with single entries during group moves.

MapView now groups drag operations: it captures start positions, suppresses individual entries, and on drag end pushes one combined group entry