Keep browser decision fixtures valid through live refresh

Reusable testing lesson from Shield Required Review rollback (COR-4076 / PR #804, observed 2026-09-08): a browser test that opens a review modal, then directly mutates its child to Failed before clicking Decline tests a stale-UI race rather than a stable customer journey. Restoring child-derived status legitimately removes the controls on refresh. Keep the browser fixture reviewable through the user action and assert persisted outcomes/evidence; test already-failed-child handling separately at the API boundary, including no duplicate child-transition notifications. Source: support-review-workflows.spec.ts and review/route.webhook.test.ts, commit 34199df6; original failing Actions run 34211039984. This preserves the edge-case proof without forcing obsolete UI behavior or disabling live updates.