Add Niteshift Dials SDK for runtime design prototyping

Introduces a complete design dials system that allows designers and PMs
to adjust UI parameters at runtime without code changes.

**Dials SDK (`packages/dials/`):**
- useDynamicColor: Color values with design system integration
- useDynamicSpacing: Spacing/padding/margin controls
- useDynamicVariant: Discrete choice selections
- useDynamicBoolean: Toggle/feature flag controls
- useDynamicNumber: Numeric values with min/max/step
- DialsOverlay: Compact Leva-inspired UI (Ctrl+D to toggle)
- DialsProvider: React context for dial state management
- Design manifest integration for design system tokens

**App Integration:**
- Added DialsProvider to app Providers
- Example dials on WebsitePage (metrics bar, panels, navigation)
- MetricCard component with adjustable typography dials
- TypeScript manifest at src/config/niteshift-manifest.ts

**Documentation:**
- Comprehensive CLAUDE.md section on dials usage
- Best practices for preserving original appearance
- Examples for all dial types

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

packages/dials/vitest.config.ts

@@ -0,0 +1,11 @@
+import { defineConfig } from 'vitest/config';
+import react from '@vitejs/plugin-react';
+
+export default defineConfig({
+  plugins: [react()],
+  test: {
+    globals: true,
+    environment: 'jsdom',
+    setupFiles: ['./src/__tests__/setup.ts'],
+  },
+});