{% comment %}
Scoped toast host for the approval surfaces (publish tab, composer, client portal).
Fires on an `HX-Trigger: {"showToast": {tone,title,body}}` response header — htmx
dispatches a `showToast` event whose `event.detail` is the payload. tone ∈
success|info|warn|error. Self-contained: not added to base.html (app shell untouched).
Include this ONCE per page, OUTSIDE any htmx-refetched region, so a list refresh
fired by the same response doesn't tear down the toast before it's seen.
{% endcomment %}