Add Docker deployment with Traefik integration

- docker-compose.yml for container orchestration
- Dockerfile with multi-stage build (node builder + nginx)
- nginx.conf for SPA serving

Dockerfile

@@ -0,0 +1,20 @@
+# Build stage
+FROM node:20-alpine AS builder
+
+WORKDIR /app
+
+COPY package*.json ./
+RUN npm ci
+
+COPY . .
+RUN npm run build
+
+# Production stage
+FROM nginx:alpine
+
+COPY --from=builder /app/dist /usr/share/nginx/html
+COPY nginx.conf /etc/nginx/conf.d/default.conf
+
+EXPOSE 80
+
+CMD ["nginx", "-g", "daemon off;"]