Repo cleanup + mobile/UI fixes for public demo release

- Remove legacy pipeline data, notes, screenshots, backups, old scripts
- Keep only active pipeline scripts (16) with comprehensive README
- Add src/README.md documenting frontend architecture
- Overhaul main README.md as product-focused (live demo, paper, quick start)
- Fix mobile: compact header, hide utility buttons, drawer arrow direction
- Fix share page negative answer count (Math.max guard)
- Replace emoji check/x marks with Font Awesome icons in quiz tooltips
- Add inline clickable info icon on landing page
- Add hover tooltips (title attributes) to all header/control buttons
- Update .gitignore for screenshots and .omc state

Co-Authored-By: Claude (claude-opus-4-6) <noreply@anthropic.com>

Author: jeremymanning

.gitignore

@@ -267,6 +267,12 @@ review.html
 find_domain_clusters.py
 review.html
 
+# Screenshots (testing artifacts)
+*.png
+
+# oh-my-claudecode state
+.omc/
+
 # Playwright test artifacts
 test-results/
 .DS_Store