fix(deploy): 为 K3s 配置容器镜像端点

三节点 containerd 增加 Docker Hub、GHCR 与 Quay 的 DaoCloud 镜像端点，解决生产节点直连公共 Registry 超时导致 Pod sandbox 无法创建的问题。

新增逐节点滚动刷新脚本，每次等待节点重新 Ready 并实际拉取 pause 镜像后才继续，避免同时重启 etcd 成员。初始 K3s 安装也会预置同一 registries.yaml。

验证：三节点镜像端点均返回 Registry 认证响应，bash -n、ShellCheck。

scripts/cluster/bootstrap-k3s.sh

@@ -155,6 +155,8 @@ install_cluster() {
   write_node_config "$configuration_directory/hongkong.yaml" easyai-hongkong 10.77.0.2 join
   write_node_config "$configuration_directory/los-angeles.yaml" easyai-los-angeles 10.77.0.3 join \
     'easyai.io/witness=true:NoSchedule'
+  cp "$cluster_root/deploy/kubernetes/registries.yaml" \
+    "$configuration_directory/registries.yaml"
   umask 077
   cat >"$configuration_directory/etcd-s3-secret.yaml" <<EOF
 apiVersion: v1
@@ -202,7 +204,10 @@ REMOTE
     printf '%s\n' "$K3S_TOKEN" | cluster_ssh "$host" \
       'umask 077; cat >/etc/rancher/k3s/cluster-token; chmod 0600 /etc/rancher/k3s/cluster-token'
     cluster_scp "$configuration_directory/$node_name.yaml" "$host:/etc/rancher/k3s/config.yaml"
-    cluster_ssh "$host" 'chmod 0600 /etc/rancher/k3s/config.yaml'
+    cluster_scp "$configuration_directory/registries.yaml" \
+      "$host:/etc/rancher/k3s/registries.yaml"
+    cluster_ssh "$host" \
+      'chmod 0600 /etc/rancher/k3s/config.yaml /etc/rancher/k3s/registries.yaml'
   done
 
   for index in 0 1 2; do