## Summary
- Add `robots.txt`, `sitemap.xml`, and `llms.txt` endpoints so crawlers and AI agents can discover public pages
- Fix accessibility tree issues: contact form labels, semantic nav/profile dropdown buttons, cookie consent dialog ARIA, and dead `href="#"` links
- Reduce layout shift on homepage/contact via hero min-heights, trusted-by marquee sizing, and fixed cookie banner
- Add regression tests and `docs/agentic-browsing.md` for Lighthouse agentic-browsing audits
Closes#5. Also addresses overlap with #3 (sitemap + robots.txt).
## Test plan
- [x] `python manage.py test public.tests` (14 tests pass)
- [ ] Verify `GET /robots.txt`, `/sitemap.xml`, `/llms.txt` return 200 in staging/prod
- [ ] Confirm contact form labels visible and submittable on `/contact`
- [ ] Run Lighthouse `--only-categories=agentic-browsing` on homepage and contact page
- [ ] Smoke test mobile nav dropdown and cookie consent banner
Reviewed-on: #8
westfarn