feat(docker): 生产环境 DevOps 基础设施 — TLS + 备份加密 + Prometheus + Redis 持久化

新增:
- nginx/nginx.conf: TLS 1.2/1.3 终端 + HSTS/CSP 安全头 + SSE 长连接 + 50M 上传限制
- prometheus/prometheus.yml: HMS/PostgreSQL/Redis/Nginx 四指标源
- prometheus/alerts.yml: 4 组告警规则（系统/应用/数据库/Redis），含 5xx 错误率 + 内存 + 连接数
- restore.sh: 备份恢复脚本（支持加密备份解密恢复）

改进:
- backup.sh: 新增 BACKUP_PASSPHRASE 加密（AES-256-CBC）+ 完整性校验 + 恢复指引
- docker-compose.production.yml: 添加 Nginx/Prometheus/Grafana/uploads-backup 容器
- docker-compose.yml: Redis 添加 --appendonly yes 持久化
- .env.production.example: 添加 DevOps 相关环境变量模板

docker/prometheus/prometheus.yml

@@ -0,0 +1,32 @@
+global:
+  scrape_interval: 15s
+  evaluation_interval: 15s
+
+rule_files:
+  - "alerts.yml"
+
+scrape_configs:
+  - job_name: "hms"
+    metrics_path: /metrics
+    static_configs:
+      - targets: ["app:9090"]
+        labels:
+          service: "hms-server"
+
+  - job_name: "postgres"
+    static_configs:
+      - targets: ["postgres-exporter:9187"]
+        labels:
+          service: "postgresql"
+
+  - job_name: "redis"
+    static_configs:
+      - targets: ["redis-exporter:9121"]
+        labels:
+          service: "redis"
+
+  - job_name: "nginx"
+    static_configs:
+      - targets: ["nginx-exporter:9113"]
+        labels:
+          service: "nginx"