feat: integrate WebAssembly for zero-latency, offline-first color operations

Replaced REST API dependency with @valknarthing/pastel-wasm (130KB) for
complete browser-based color operations. The application is now fully
static (2.2MB total) with zero network latency and offline support.

**Key Changes:**

1. **WASM Integration:**
   - Added @valknarthing/pastel-wasm dependency (0.1.0)
   - Created lib/api/wasm-client.ts wrapper matching API interface
   - Updated lib/api/client.ts to use WASM client by default
   - All 18 color operations now run locally in browser

2. **Static Export Configuration:**
   - Changed next.config.ts output from 'standalone' to 'export'
   - Disabled image optimization for static export
   - Removed API proxy route (app/api/pastel/[...path]/route.ts)
   - Updated package.json scripts (removed dev:api, added serve)

3. **Docker Optimization:**
   - Migrated from Node.js standalone to nginx-alpine
   - Created nginx.conf with SPA routing and WASM mime types
   - Updated Dockerfile for static file serving
   - Reduced image size from ~150MB to ~25MB
   - Changed port from 3000 to 80 (standard HTTP)
   - Simplified docker-compose.yml (removed pastel-api service)

4. **Documentation Updates:**
   - Updated README.md with WASM benefits and deployment options
   - Added Key Benefits section highlighting zero-latency features
   - Rewrote deployment section for static hosting platforms
   - Updated CLAUDE.md tech stack and architecture
   - Removed obsolete docs: DEV_SETUP.md, DOCKER.md, IMPLEMENTATION_PLAN.md

**Benefits:**
- 🚀 Zero Latency - All operations run locally via WebAssembly
- 📱 Offline First - Works completely offline after initial load
- 🌐 No Backend - Fully static, deploy anywhere
- ⚡ Fast - Native-speed color operations in browser
- 📦 Small - 2.2MB total (130KB WASM, 2.07MB HTML/CSS/JS)

**Deployment:**
Can now be deployed to any static hosting platform:
- Vercel, Netlify, Cloudflare Pages (zero config)
- GitHub Pages, S3, CDN
- Self-hosted nginx/Apache
- Docker (optional, nginx-based)

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

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

docker-compose.yml

@@ -8,35 +8,14 @@ services:
     image: ghcr.io/valknarness/pastel-ui:latest
     container_name: pastel-ui
     ports:
-      - "3000:3000"
-    environment:
-      - NODE_ENV=production
-      # Runtime configuration - can be changed without rebuilding
-      - PASTEL_API_URL=${PASTEL_API_URL:-http://pastel-api:3001}
+      - "80:80"
     restart: unless-stopped
     healthcheck:
-      test: ["CMD", "curl", "-f", "http://localhost:3000/"]
+      test: ["CMD", "wget", "--no-verbose", "--tries=1", "--spider", "http://localhost/"]
       interval: 30s
       timeout: 10s
       retries: 3
-      start_period: 40s
-
-  pastel-api:
-    image: ghcr.io/valknarness/pastel-api:latest
-    container_name: pastel-api
-    ports:
-      - "3001:3001"
-    environment:
-      - RUST_LOG=info
-      - PORT=3001
-      - HOST=0.0.0.0
-    restart: unless-stopped
-    healthcheck:
-      test: ["CMD", "curl", "-f", "http://localhost:3001/api/v1/health"]
-      interval: 30s
-      timeout: 10s
-      retries: 3
-      start_period: 10s
+      start_period: 5s
 
 networks:
   default: