Function lumen_app_run_headless 

#[unsafe(no_mangle)]
pub unsafe extern "C" fn lumen_app_run_headless(
    app: *mut LumenApp,
    ticks: u32,
) -> LumenStatus

Consume the app handle and drive ticks main-schedule ticks without opening a window or GPU surface (ABI 0.3). After this returns, app is freed - do not call lumen_app_free on the same pointer.

This is the headless / CI entry point: it builds the full app (same plugin stack, scripts, and reactive bindings as lumen_app_run) and calls App::tick() ticks times, then returns. Signal round-trips, script execution, <for> / <if> reconciliation, and typed-property draining all run; there is no windowing, no input source, and no GPU-backed rendering. Native click handlers registered with lumen_app_on_click will not fire (no input is injected in headless mode). Pass ticks = 0 to build-and-drop (validates the app loads).