Function post_create_floating_window 

pub fn post_create_floating_window(
    state: &Arc<AppState>,
    args: &OpenFloatingPaneArgs,
    window_label: &str,
)

Posts the create-floating-window task to the CEF UI thread. Returns immediately. Mirrors the shape of ui_tasks::post_create_window but goes through this module so the path is grep-able.