M3's accessibility page forbids it outright: an actioned snackbar has to wait
for the person to read it and reach its action. An entry with an action and no
timeout of its own is now untimed, the close button it already draws being the
way out; a timeout written out still wins. Plan step 11, actions.md ACT-03.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Qwx5USif3wFFmxtHg5U1g9