A successful Windows termination request can end the process before Node publishes exitCode or signalCode. If a child error wins the shutdown race, give that accepted exit a bounded observation window before escalating or reporting fallback refusal.
Cover a delayed real exit edge, preserve prompt refusal behavior for a genuinely live child, and document the launcher grace without weakening the complete stdio and parser drain boundary.
Treat a fallback kill refusal as successful termination when the child already carries an OS exit marker. Windows maps Node's supported signal names to forced termination, so the requested signal can end the process between the launcher error race and its fallback SIGKILL.
Drain inherited stdio, the ACP parser, and in-flight callbacks before propagating the original child error in either exit-race path. Preserve AggregateError reporting only for a refused fallback while the process is still live, and add a deterministic cross-platform regression for that ordering.