#6629 Make undo redo work without code pane being open (#7511)

* move useHotkey for undo/redo into App

* _editorView should be private

* get editorView should be a real get method for consistency

* resolve tsc errors

* fmt

* setView, setState are not exposed

* make undo work without editorview when kcl pane is closed

* lint

* circular deps

* resolve circular deps

* fix undo being 1 step late

* unrelated console.warn removed

* fix undo when code pane is closed during editing

* cleanup

* allow undo to get beyond when code editor has been mounted

* fix up clearHistory

* add test for testing  Undo with closed code pane

src/lib/singletons.ts

@@ -69,6 +69,7 @@ export const kclManager = new KclManager(engineCommandManager, {
 // method requires it for the current ast.
 // CYCLIC REF
 editorManager.kclManager = kclManager
+editorManager.codeManager = codeManager
 
 // These are all late binding because of their circular dependency.
 // TODO: proper dependency injection.