Design decisions

Why OPSX works the way it does.

<!-- WIP, on the todo list: this page is not written yet and is held back from the site (its entry is commented out in website/docs.sync.config.mjs, 2026-08-21). The file stays so the structure and inbound links survive; re-list it in the sync config once the prose lands. --> <!-- Skeleton: heading only. Split from reference/architecture.md on 2026-08-10. message-map.md routes "the workflow is fluid, actions not phases" here. -->