Validate unpublish versions with the existing publish semver predicate before reading or mutating storage. Reject build metadata in publish version keys at the document validation boundary, preserving manifest normalization for archives whose versions carry build metadata. Catch startup, forwarding, and container-access failures in the documented Cloudflare Worker and return a generic availability response with a retry delay. Exercise the actual deployment snippet with mocked container failures. Closes https://github.com/zkochan/pnpm-tasks/issues/19.