feat(cluster): 接入深圳专用 Worker 节点

新增深圳 K3s agent 与四节点 WireGuard 全互联接入脚本，将深圳归入香港逻辑 Worker 池并用污点限制为 Worker 专用。\n\n生产验收支持宁波 0、香港逻辑池 2 的双物理节点基线，补充副本拓扑分散、容量档位、链路巡检和零副本站点校验。\n\n已通过 Go 全量测试、go vet、govulncheck、迁移安全检查、ShellCheck、发布脚本测试、前后端 lint/test/build、Compose 与 Kubernetes 渲染校验。

deploy/kubernetes/production/application.yaml

@@ -458,6 +458,11 @@ spec:
       nodeSelector:
         easyai.io/site: ningbo
         easyai.io/workload: "true"
+      tolerations:
+        - key: easyai.io/worker-only
+          operator: Equal
+          value: "true"
+          effect: NoSchedule
       securityContext:
         runAsNonRoot: true
         runAsUser: 10001
@@ -617,6 +622,11 @@ spec:
       nodeSelector:
         easyai.io/site: hongkong
         easyai.io/workload: "true"
+      tolerations:
+        - key: easyai.io/worker-only
+          operator: Equal
+          value: "true"
+          effect: NoSchedule
       securityContext:
         runAsNonRoot: true
         runAsUser: 10001