fix: 仅获取已启用的聊天模型

在获取聊天模型列表时新增 IsEnabled 条件过滤，避免返回未启用的模型，确保模型选择结果正确。

Yi.Abp.Net8/module/ai-hub/Yi.Framework.AiHub.Application/Services/Chat/AiChatService.cs

@@ -94,6 +94,7 @@ public class AiChatService : ApplicationService
     public async Task<List<ModelGetListOutput>> GetModelAsync()
     {
         var output = await _aiModelRepository._DbQueryable
+            .Where(x=>x.IsEnabled==true)
             .Where(x => x.ModelType == ModelTypeEnum.Chat)
             .Where(x => x.ModelApiType == ModelApiTypeEnum.OpenAi)
             .OrderByDescending(x => x.OrderNum)