Function toggle_sidebar 

pub fn toggle_sidebar(host: RNode) -> bool

Show/hide the sidebar pane of the navigation host host: the behavior behind the sidebar affordance a nav host contributes for itself (day_spec::SIDEBAR_TOGGLE_ID). false when the toolkit has no pane to toggle there. The item’s action makes this call, and dayscript’s toolbar: step presses the item like any other, so a walkthrough drives the same path a click does (docs/toolbars.md).