Function handle_ui_browser_act 

pub(crate) async fn handle_ui_browser_act(
    __arg0: State<AppState>,
    caller: Option<Extension<Caller>>,
    __arg2: Json<UiBrowserActRequest>,
) -> impl IntoResponse

POST /api/v1/ui/browser/act — backs BrowserClick, BrowserFill, BrowserSelect and BrowserCheck (spec §4.2).