I want the level editor's stateful Editor object to support redoing an undone edit with Editor.redo()…

I want the level editor's stateful Editor object to support redoing an undone edit with Editor.redo()…: a task in MiMo-V2.6-RL-harbor-code: MiMo-V2.6-RL Code (Harbor) (Harbor dataset). Users should also be able to invoke the same redo command from the editor UI: the menubar should include a Redo…

The task

Users should also be able to invoke the same redo command from the editor UI: the menubar should include a `Redo` button, and the keyboard shortcuts Ctrl+Y and Ctrl+Shift+Z should call redo while the editor is active. If a user undoes an edit and then performs a new edit instead of redoing, the old redo history…

Part of FineEnvs/MiMo-V2.6-RL-harbor-code.