A production rollout exposes a contract mismatch between the UI boundary and the owning service. The affected area is feature flags.
Repair the feature flags command handling implementation so it accepts first operations, recognizes safe repeats, and rejects key reuse with a different payload.
Evidence
- Affected surface: Full-stack frontend focus / feature flags.
- Observed failure family: enforce idempotent operations.
- Scope policy: zoneState must equal healthy.