Mirrors the detail-drawer move: the .app-toast-stack container is no
longer lazy-created in JS on first toast, instead it lives in
templates/partials/app-toast-stack.phtml and is mounted once in
default.phtml alongside the confirm dialog. The aria-live attribute now
sits in the SSR markup so screen readers register the live region from
page load, not from the first toast.
getToastStack() drops to a plain querySelector and warns via warnOnce
when the partial is missing instead of constructing a fallback container.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
