chore(deploy): 生产 docker compose + scratch Dockerfile + 部署文档

- docker-compose.prod.yml：仅 api 绑 127.0.0.1:8120，DB/redis/minio 不暴露，restart=unless-stopped，凭据走 .env
- api/Dockerfile.prod：runtime 改用 scratch + 拷贝 ca-certs（gcr.io/distroless 不可达环境），Go 模块走 goproxy.cn
- .env.example / docs/deploy.md

Co-Authored-By: Devin AI <158243242+devin-ai-integration[bot]@users.noreply.github.com>

docker-compose.prod.yml

@@ -0,0 +1,61 @@
+name: goods
+services:
+  postgres:
+    image: postgres:16-alpine
+    restart: unless-stopped
+    environment:
+      POSTGRES_USER: ${POSTGRES_USER}
+      POSTGRES_PASSWORD: ${POSTGRES_PASSWORD}
+      POSTGRES_DB: ${POSTGRES_DB}
+    volumes:
+      - pgdata:/var/lib/postgresql/data
+    healthcheck:
+      test: ["CMD-SHELL", "pg_isready -U ${POSTGRES_USER}"]
+      interval: 5s
+      timeout: 5s
+      retries: 10
+
+  redis:
+    image: redis:7-alpine
+    restart: unless-stopped
+    healthcheck:
+      test: ["CMD", "redis-cli", "ping"]
+      interval: 5s
+      timeout: 5s
+      retries: 10
+
+  minio:
+    image: minio/minio:latest
+    restart: unless-stopped
+    command: server /data --console-address ":9001"
+    environment:
+      MINIO_ROOT_USER: ${MINIO_ROOT_USER}
+      MINIO_ROOT_PASSWORD: ${MINIO_ROOT_PASSWORD}
+    volumes:
+      - miniodata:/data
+    healthcheck:
+      test: ["CMD", "mc", "ready", "local"]
+      interval: 5s
+      timeout: 5s
+      retries: 10
+
+  api:
+    build:
+      context: ./api
+      dockerfile: Dockerfile.prod
+    restart: unless-stopped
+    depends_on:
+      postgres:
+        condition: service_healthy
+      redis:
+        condition: service_healthy
+    environment:
+      OPENGOODS_ADDR: ":8080"
+      OPENGOODS_DATABASE_URL: "postgres://${POSTGRES_USER}:${POSTGRES_PASSWORD}@postgres:5432/${POSTGRES_DB}?sslmode=disable"
+      OPENGOODS_REDIS_URL: "redis://redis:6379/0"
+    ports:
+      - "127.0.0.1:8120:8080"
+
+volumes:
+  pgdata:
+  miniodata: