Function dispatch 

pub fn dispatch(
    node: &Node,
    ctx: &ExecutorContext<'_>,
) -> Result<NodeOutcome, DispatchError>

Dispatch one node end-to-end.

Emits node.started on entry, runs the node body, runs any attached gate, and emits exactly one terminal event (node.completed or node.failed). The returned NodeOutcome mirrors the terminal event so the runner can feed the scheduler without re-reading the event log.