docs: add runbooks and Kubernetes Helm Chart

Add 6 runbook documents:
- 服务启动 (Service Startup)
- 服务停止 (Service Shutdown)
- 配置更新 (Configuration Update)
- 日志分析 (Log Analysis)
- 备份恢复 (Backup & Recovery)
- 安全事件 (Security Incident)

Add Kubernetes Helm Chart:
- Chart.yaml, values.yaml
- Deployment with health checks
- Ingress with TLS support
- PVC for data persistence
- PDB for high availability
- HPA for autoscaling
- ServiceAccount configuration

Add cron-backup.conf for automated backup scheduling.

kubernetes/user-management/templates/hpa.yaml

@@ -0,0 +1,32 @@
+{{- if .Values.autoscaling.enabled }}
+apiVersion: autoscaling/v2
+kind: HorizontalPodAutoscaler
+metadata:
+  name: {{ include "user-management.fullname" . }}
+  labels:
+    {{- include "user-management.labels" . | nindent 4 }}
+spec:
+  scaleTargetRef:
+    apiVersion: apps/v1
+    kind: Deployment
+    name: {{ include "user-management.fullname" . }}
+  minReplicas: {{ .Values.autoscaling.minReplicas }}
+  maxReplicas: {{ .Values.autoscaling.maxReplicas }}
+  metrics:
+    {{- if .Values.autoscaling.targetCPUUtilizationPercentage }}
+    - type: Resource
+      resource:
+        name: cpu
+        target:
+          type: Utilization
+          averageUtilization: {{ .Values.autoscaling.targetCPUUtilizationPercentage }}
+    {{- end }}
+    {{- if .Values.autoscaling.targetMemoryUtilizationPercentage }}
+    - type: Resource
+      resource:
+        name: memory
+        target:
+          type: Utilization
+          averageUtilization: {{ .Values.autoscaling.targetMemoryUtilizationPercentage }}
+    {{- end }}
+{{- end }}