Add designbook integration tooling + stack-adapter workplan

- designbook/ local mirror of the Claude Design project, with conventions
  (@dsCard/manifest) and freshness marker docs.
- make designbook-sync + scripts/designbook-sync.mjs: record what a sync
  changed into RecentChanges.md, grouped by layer, with last /design-sync time.
- make designbook-check + scripts/check_designbook_staleness.py: llm-connect
  (claude-code adapter) backend that detects when the cloud designbook moved
  ahead and warns the local mirror is outdated.
- .design-sync/config.json: recorded target project pin (WhyNot Design System).
- WHYNOT-WP-0002: workplan for a technology-neutral designbook IR with
  scaffold+drift-detect stack adapters (Lit reference).
- gitignore Python artifacts.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

.gitignore

@@ -8,6 +8,10 @@ playwright-report
 test-results
 /tests/visual/**/__diff__
 
+# Python (scripts/check_designbook_staleness.py)
+__pycache__
+*.pyc
+
 # Editor
 .vscode
 .idea