Demolition step ahead of the site rationalization (App Router + shared
design system foundation to follow).

- Remove Dunbar entirely (pages, components, lib, tests); it's folding
  into a separate project. UX learnings preserved at
  docs/dunbar-design-learnings.md.
- Prune 6 now-unused deps: d3-force, d3-zoom, minisearch,
  react-force-graph(-2d), snowball-stemmers, stopword.
- Fix 3 production bugs in layout.js: drop the http://localhost:8097
  React DevTools script, replace the create-next-app template OG image
  with the site profile image, and compute the footer year dynamically.
- Delete dead files: pages/parvagues.js.backup, the unused HeroVariants.
- Add CLAUDE.md documenting the codebase and the redesign state.

Build green (yarn build, 40 routes). Note: this removes all test
coverage (it was all Dunbar's) — to be re-established in Phase 2.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>