Function kj_runtime_scene_json 

#[unsafe(no_mangle)]
pub extern "C" fn kj_runtime_scene_json(
    handle: KjHandle,
    output: *mut u8,
    capacity: usize,
    required: *mut usize,
    error: *mut u8,
    error_capacity: usize,
    error_required: *mut usize,
) -> KjStatus

Serializes the authoritative scene document as UTF-8 JSON.