## Context

`Primer::Alpha::ActionList#before_render` assigns `aria-labelledby = heading.title_id` unconditionally whenever a heading is present (`openproject-primer_view_components` 0.91.1, `app/components/primer/alpha/action_list.rb:178`). Accessible-name computation follows `aria-labelledby` references even when the referenced element is hidden, so a group rendered with a hidden heading is still announced under that Begin of the insertionheading'sEnd of the insertion Begin of the deletion heading'sEnd of the deletion text. Begin of the insertion
End of the insertion Begin of the deletion
End of the deletion Found during #AGILE-364: the Backlogs card ActionMenu renders its batch group heading with `hidden: true` for a one-card scope, yet screen readers announce the group as Begin of the insertion"0End of the insertion Begin of the deletion "0End of the deletion selected work Begin of the insertionpackages"End of the insertion Begin of the deletion packages"End of the deletion (or a stale count after a batch collapses). #AGILE-364 ships a client-side workaround that strips and restores the attribute; that workaround should become unnecessary.

## Goal

Fix the fork (`opf/primer_view_components`) so a hidden heading never contributes an accessible group name, and propose the same change upstream to `primer/view_components`. Either omit `aria-labelledby` (and `aria-describedby` for a hidden subtitle) while the heading is hidden, or hide the heading in an accname-safe way; a heading revealed at runtime must get its naming relationship back without a re-render.

## Acceptance criteria

Begin of the insertion* End of the insertion Begin of the deletion -End of the deletion A group whose heading is rendered hidden exposes no accessible name or description derived from that heading. Begin of the insertion

* End of the insertion Begin of the deletion
-End of the deletion Revealing the heading restores the `aria-labelledby`/`aria-describedby` relationships without server round-trip. Begin of the insertion

* End of the insertion Begin of the deletion
-End of the deletion Component/system test coverage for the hidden and revealed states, including accessible-name assertions. Begin of the insertion

* End of the insertion Begin of the deletion
-End of the deletion PR opened against `opf/primer_view_components`; Begin of the insertion

* End of the insertion Begin of the deletion issue or PR filed against `primer/view_components` referencing the accname behavior.
-End of the deletion Follow-up note on #AGILE-364 (or its successor) so the client-side attribute workaround can be removed once the fix ships.