Why: Live E2E on the dev instance - the model keyed section children
as an object map (children.item.*), the strict decode rejected it, and
the page fell back to a file artifact; the guidance fix made the model
call present, this closes the remaining shape gap.
Evidence: genui suite green incl. the reproduction case; post-deploy
E2E rerun recorded in the Dev task.
Impact: Repair strategy only; validation unchanged.
Refs: Dev task fix/genui-page-visibility (E2E follow-up)