logicalKeys property Null safety
The list of "logical" keys. This has nothing to do with the UI; The order of the operations in this list determines the externalized form of the operations in the calculator's storage (the opcodes). It also determines the displayed appearance of operations in program mode, whether the calculator is in portrait or landscape orientation.
Changing the order here would render old JSON files of the calculator's state obsolete.
@override late final List<List<MKey<OT>?>> logicalKeys = _getLogicalKeys();