fix: 修复 AdsModel 初始化报空的 BUG

Runtime/GuruCore/Runtime/Ads/ADServiceBase.cs

@@ -37,6 +37,16 @@ namespace Guru
         private AdsModel _model;
         private AdsInitSpec _initSpec = null;
 
+        public AdsModel Model
+        {
+            get
+            {
+                if (_model == null) _model = AdsModel.Create();
+                return _model;
+            }
+        }
+
+
         /// <summary>
         /// 启动广告服务
         /// </summary>
@@ -50,7 +60,7 @@ namespace Guru
             _initSpec = initSpec;
             _isServiceStarted = true;
             _onSdkInitReady = callback;
-            _model = AdsModel.Create();
+            if(_model == null) _model = AdsModel.Create();
             this.Log("AD SDK Start Init");
 
             //--------------  初始化回调 ------------------
@@ -116,8 +126,8 @@ namespace Guru
 
         public bool IsBuyNoAds
         {
-            get => _model.BuyNoAds;
-            set=> _model.BuyNoAds = value;
+            get => Model.BuyNoAds;
+            set => Model.BuyNoAds = value;
         }