Fixes a macOS flake in timeout forensics where a killed sampler descendant that was still visible as a zombie process was incorrectly treated as still running.
Adds a regression test covering unreaped zombie children.
On macOS, checks the kernel process state via proc_pidinfo and treats SZOMB status as stopped.
Adds a benchmark slice descriptor JSON for the land-sampler-zombie-flake case.
Confidence Score: 5/5
The PR appears safe to merge.
Summary
Updates the sampler timeout test helper to recognize unreaped zombies on macOS.
The sampler zombie slice is marked as non-ranking harness work.
macOS timeout checks now stop waiting for zombie processes.
