feat: implement docker infrastructure (US-001)

- Add docker-compose.yml with postgres, redis, api, and web services
- Add multi-stage Dockerfile for API (Python 3.11)
- Add multi-stage Dockerfile for web (Node.js 20 + nginx)
- Add Makefile with common development commands
- Add .env.example with all required environment variables
- Add placeholder pyproject.toml and package.json for builds
- Configure health checks for all services
- Setup persistent volumes for postgres, redis, and repos
- Run services as non-root users

Makefile

@@ -0,0 +1,94 @@
+.PHONY: help up down logs migrate test lint clean build
+
+# Default target
+help:
+	@echo "Headquarter Development Commands"
+	@echo "================================"
+	@echo "make up       - Start all services"
+	@echo "make down     - Stop all services"
+	@echo "make logs     - View service logs"
+	@echo "make migrate  - Run database migrations"
+	@echo "make test     - Run test suites"
+	@echo "make lint     - Run linting"
+	@echo "make build    - Build all Docker images"
+	@echo "make clean    - Remove containers and volumes"
+	@echo "make shell    - Open shell in API container"
+
+# Start services
+up:
+	docker compose up -d
+	@echo "Services starting..."
+	@echo "API: http://localhost:8000"
+	@echo "Web: http://localhost:3000"
+	@echo "Postgres: localhost:5432"
+	@echo "Redis: localhost:6379"
+
+# Stop services
+down:
+	docker compose down
+
+# View logs
+logs:
+	docker compose logs -f
+
+# View specific service logs
+logs-api:
+	docker compose logs -f api
+
+logs-web:
+	docker compose logs -f web
+
+logs-db:
+	docker compose logs -f postgres
+
+# Run database migrations
+migrate:
+	docker compose exec api alembic upgrade head
+
+# Create new migration
+migration:
+	docker compose exec api alembic revision --autogenerate -m "$(message)"
+
+# Run tests
+test:
+	docker compose exec api pytest -v
+
+# Run linting
+lint:
+	docker compose exec api ruff check .
+	docker compose exec api mypy .
+	cd apps/web && npm run lint
+
+# Type checking
+typecheck:
+	docker compose exec api mypy .
+	cd apps/web && npm run typecheck
+
+# Build all images
+build:
+	docker compose build
+
+# Build specific service
+build-api:
+	docker compose build api
+
+build-web:
+	docker compose build web
+
+# Clean up
+clean:
+	docker compose down -v --remove-orphans
+	docker system prune -f
+
+# Open shell in API container
+shell:
+	docker compose exec api /bin/sh
+
+# Database shell
+db-shell:
+	docker compose exec postgres psql -U $(POSTGRES_USER) -d $(POSTGRES_DB)
+
+# Health check
+health:
+	@echo "Checking service health..."
+	@docker compose ps