Renders LoginPage with form.rateLimited=true and asserts that the role="alert" div (clock icon + error message) is visible in the browser. Previously only the form action's rateLimited=true return value was tested; now the rendered UI is also verified. Addresses Sara Concern 4 / Elicit open question from PR #617 review. Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>