feat(commands): add app state dispatcher foundation

editor/index.ts

@@ -1 +1,4 @@
 export type { AppState, EditorState, SelectionState, ViewportState } from "./state";
+export { createInitialAppState, initialEditorState } from "./initial-state";
+export type { AppStore, StateListener } from "./store";
+export { createAppStore } from "./store";