A production rollout exposes a contract mismatch between the UI boundary and the owning service. The affected area is auth session.
Repair the auth session tests implementation so it classifies stable, flaky, and consistently failing tests from repeated independent runs.
Evidence
- Affected surface: Full-stack backend focus / auth session.
- Observed failure family: triage an unreliable test suite.
- Scope policy: cohort must equal stable.