feat: the node itself requires an owner passkey (shared by agent and probe) and reports it; the panel derives the account and passkey it is bound to [CI]

backend/agent/src/MoShiro.Agent/AgentConfig.cs

@@ -45,6 +45,10 @@ public sealed class FleetSection
 
     [JsonPropertyName("identity_dir")]
     public string IdentityDir { get; set; } = "/etc/moshiro";
+
+    /// <summary>节点自己要求有属主（passkey）：没有就不运行。见 <c>OwnerGuard</c>。</summary>
+    [JsonPropertyName("require_owner")]
+    public bool RequireOwner { get; set; } = true;
 }
 
 public sealed class ListenSection