onLog property
Where a resource's output goes as it is produced.
Wired to the agent's own logger, so an apply travels the path the node log
already takes and an operator can watch it happen. Each line is tagged with
the resource that produced it — [formula:dart] … — because the stream
carries everything the node says and a reader needs to pick one run out of
it.
Implementation
final void Function(String line)? onLog;