The ordered canonical stage ids for a pipeline id, or an empty list for an
unknown / absent id (so a consumer degrades gracefully to whatever stages it
actually observes). The ids are the stable pipeline identifiers set by the
scholar / scribe factories.
The ordered canonical stage ids for a pipeline id, or an empty list for an unknown / absent id (so a consumer degrades gracefully to whatever stages it actually observes). The ids are the stable pipeline identifiers set by the scholar / scribe factories.