chore: initial scaffold of KDC Design System

Initial repository scaffold:
- design.md (google-labs-code/design.md format) as canonical token + guidelines source
- brand assets, foundations, tokens (W3C-style JSON)
- 12 component primitives, each with labeled anatomy.svg and spec README
- light / dark / high-contrast themes, web/mobile/email/print/presentation templates
- docs (getting started, principles, a11y, voice & tone, contributing)
- runnable web example, token build script stub, CI placeholder

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

assets/icons/ui/README.md

@@ -0,0 +1,7 @@
+# Icons · ui
+
+Place 24x24 SVG icons for the **ui** set here. Each icon should:
+
+- Use `viewBox="0 0 24 24"`
+- Stroke or fill `currentColor`
+- Have descriptive `<title>` and `aria-*` attributes when used directly