The markers are touched mid-script, so runPoint's continuation chain (child
exit → merge → the listener's detached .then) can still be in flight when the
marker poll resolves; a vitest worker that exits first leaves the inject
condition's short-circuit path uncounted. Observed as a CI-only 99.03%
branch-coverage flake on hooks-claude — surfaced by this branch shifting suite
timing, latent before it. Two macrotask rounds pin the path deterministically.