feat(03-01): add GwHealthCheckConfig value object

- Created health check configuration value object
- Includes Enabled, Path, IntervalSeconds, TimeoutSeconds fields
- Matches YARP ClusterConfig health check structure

Fengling.Platform.Domain/AggregatesModel/GatewayAggregate/GwHealthCheckConfig.cs

@@ -0,0 +1,27 @@
+namespace Fengling.Platform.Domain.AggregatesModel.GatewayAggregate;
+
+/// <summary>
+/// 健康检查配置（值对象）
+/// </summary>
+public class GwHealthCheckConfig
+{
+    /// <summary>
+    /// 是否启用健康检查
+    /// </summary>
+    public bool Enabled { get; set; }
+    
+    /// <summary>
+    /// 健康检查路径
+    /// </summary>
+    public string? Path { get; set; }
+    
+    /// <summary>
+    /// 检查间隔（秒）
+    /// </summary>
+    public int IntervalSeconds { get; set; } = 30;
+    
+    /// <summary>
+    /// 超时时间（秒）
+    /// </summary>
+    public int TimeoutSeconds { get; set; } = 10;
+}