Drop story 28, renumber 30-33 to 28-31, add story 31 (View Upcoming
Stories), and extend .ignore for .claude/ and .story_kit/ directories.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Add end-to-end coverage tracking: backend collects vitest coverage,
records metrics with threshold/baseline tracking, and blocks acceptance
on regression. Frontend displays coverage in gate/review panels with
a "Collect Coverage" button. Includes 20 Rust tests, 17 Vitest tests,
and 14 Playwright E2E tests.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>