Function register_node 

pub fn register_node<C: Component>(
    recorder: &mut dyn NodeRuntime,
    executor: &mut Executor<'static>,
) -> NodeResult<()>

Run component registration against a metadata recorder, on executor.

phase-483 W3: registration creates real nodes, so it needs an executor even on the probe’s road — open one on the metadata backend (ExecutorConfig::new("").rmw("metadata")). The recorder receives every declaration exactly as it did when it was the whole runtime.