docs: initial project setup and documentation

Add comprehensive documentation and planning for Pastel UI:
- Complete architecture design using Next.js 16 and Tailwind CSS 4
- Detailed development guide (CLAUDE.md) with all patterns and conventions
- Feature-rich README with keyboard shortcuts and export formats
- Project structure and technology stack decisions

Features planned:
- Color playground with multi-format support
- Palette generation (harmony, distinct, gradient)
- Accessibility tools (WCAG, color blindness simulation)
- Named colors explorer (148 CSS/X11 colors)
- Batch operations with CSV/JSON import/export
- Command palette (Cmd+K) and keyboard shortcuts
- Dark/light mode with system preference detection
- Shareable links with URL state

Tech stack:
- Next.js 16 with App Router and Server Components
- React 19 with latest concurrent features
- Tailwind CSS 4 with CSS-first configuration
- TypeScript strict mode
- React Query for server state
- Zustand for client state
- Framer Motion for animations

Ready for implementation phase.

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

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

.gitignore

@@ -0,0 +1,57 @@
+# Dependencies
+node_modules/
+.pnp/
+.pnp.js
+
+# Testing
+coverage/
+.nyc_output/
+playwright-report/
+test-results/
+
+# Next.js
+.next/
+out/
+build/
+dist/
+
+# Production
+*.tsbuildinfo
+next-env.d.ts
+
+# Misc
+.DS_Store
+*.pem
+Thumbs.db
+
+# Debug
+npm-debug.log*
+yarn-debug.log*
+yarn-error.log*
+pnpm-debug.log*
+lerna-debug.log*
+
+# Local env files
+.env
+.env*.local
+.env.production
+
+# Vercel
+.vercel
+
+# TypeScript
+*.tsbuildinfo
+
+# IDE
+.vscode/
+.idea/
+*.swp
+*.swo
+*~
+
+# Logs
+logs/
+*.log
+
+# Turbopack
+.turbo/