setSelected(editor) {
    this.#currentDrawingSession?.commitOrRemove();
    for (const ed of this.#selectedEditors) {
      if (ed !== editor) {
        ed.unselect();
      }
    }
    this.#selectedEditors.clear();

    this.#selectedEditors.add(editor);
    editor.select();
    this.#dispatchUpdateUI(editor.propertiesToUpdate);
    this.#dispatchUpdateStates({
      hasSelectedEditor: true,
    });
  }
Set the last selected editor.
@param {AnnotationEditor} editor