WordPress batch mutation audit

Review the correctness boundary of work split across requests or workers. Treat "the request returned success" and "the intended dataset reached the intended state exactly once" as different claims. Do not use this skill for read-only pagination; use it when rows, files, remote systems, or durable state change.

Audit workflow

1. Identify the unit of work: object ID, meta ID, custom-table primary key, file, remote delivery, or immutable snapshot row.
2. Trace selection, mutation, progress persistence, response, retry, and cleanup.
3. Model a timeout before commit, after commit but before response, and halfway through a batch.
4. Model two tabs, two admins, cron overlap, and a manual retry running together.
5. Verify every mutation result and distinguish no-op from failure.
6. Report the final-state invariant, not only individual code smells.

Critical checks