Codex review: version existence alone does not prove the npm registry
serves the tarball this tag's preflight built — the same version could
have been published from a different artifact and npm versions are
immutable. The resume resolver now downloads the preflight manifest,
requires its releaseSha to match the target, and compares the published
registry tarball's sha256 against the manifest before skipping the core
dispatch; mismatches abort with correction-tag guidance.