docs: update TODO.md - mark docker-compose task complete (iteration 16)

TODO.md

@@ -31,7 +31,7 @@
 ### DevOps
 - [x] Create Dockerfile for backend
 - [x] Create Dockerfile for frontend (nginx)
-- [ ] Write docker-compose.yml
+- [x] Write docker-compose.yml
 - [ ] Test local deployment
 
 ### Documentation
@@ -45,6 +45,21 @@
 ## ✅ Completed Tasks
 
 ### 2026-03-24
+- **Docker Compose orchestration** (Iteration 16)
+  - Created docker-compose.yml with backend and frontend services
+  - Backend service: Node.js API on port 3000 with named volume for SQLite persistence (recipe-data:/app/data)
+  - Frontend service: nginx on port 8080, depends on backend health check
+  - Configured nginx to proxy /api/* requests to backend service (http://backend:3000)
+  - Updated frontend API client (services/api.ts) to use relative URLs (/api instead of http://localhost:3000/api)
+  - Added Vite dev server proxy configuration for local development (proxies /api to localhost:3000)
+  - Implemented health checks for both services (backend: GET /api/recipes, frontend: GET /health)
+  - Configured restart policies (unless-stopped) and service dependencies
+  - Created internal Docker network (recipe-network) for service communication
+  - Added comprehensive documentation in docs/docker-compose.md (architecture, usage, troubleshooting, testing)
+  - Supports both local development (npm run dev with Vite proxy) and production deployment (Docker Compose)
+  - Verified: YAML syntax valid, all 5 files committed
+  - Next: Test local deployment (docker compose up -d && docker compose ps)
+
 - **Frontend Dockerfile implementation** (Iteration 15)
   - Created multi-stage Dockerfile for frontend build and deployment
   - Builder stage: Node.js 22 Alpine with npm ci, TypeScript compilation, Vite production build