Function cmd_benchmark 

pub(crate) fn cmd_benchmark(
    preset_path: PathBuf,
    frames: u32,
    width: u32,
    height: u32,
    mesh_size: (u32, u32),
) -> Result<()>

Run frames frames through the engine and print per-frame timing statistics. The first frame is excluded from the summary (compile + upload one-shot costs would skew the mean).