Field renders its visible label as <label htmlFor>, but that only
associates with labelable elements (input, select, ...), not the
div[role="group"] DeliverCheckboxes renders. The checkbox group had
no accessible name for assistive tech.
Field now stamps an id on its label (`${htmlFor}-label`) and
DeliverCheckboxes references it via aria-labelledby, so the group
picks up the same visible label text instead of duplicating it.
Addresses review feedback on PR #73886.
owner
3a8d95a93b