fix: Handle null response metadata and models in GetDiscountProductsQueryHandler

src/BackOffice.BFF.Application/DiscountProductCQ/Queries/GetDiscountProducts/GetDiscountProductsQueryHandler.cs

@@ -41,7 +41,7 @@ public class GetDiscountProductsQueryHandler : IRequestHandler<GetDiscountProduc
 
         return new GetDiscountProductsResponseDto
         {
-            MetaData = new MetaData
+            MetaData = response.MetaData != null ? new MetaData
             {
                 CurrentPage = response.MetaData.CurrentPage,
                 TotalPage = response.MetaData.TotalPage,
@@ -49,8 +49,8 @@ public class GetDiscountProductsQueryHandler : IRequestHandler<GetDiscountProduc
                 TotalCount = response.MetaData.TotalCount,
                 HasPrevious = response.MetaData.HasPrevious,
                 HasNext = response.MetaData.HasNext
-            },
-            Products = response.Models.Select(p => new DiscountProductDto
+            } : new MetaData(),
+            Products = response.Models?.Select(p => new DiscountProductDto
             {
                 Id = p.Id,
                 Title = p.Title,
@@ -62,8 +62,8 @@ public class GetDiscountProductsQueryHandler : IRequestHandler<GetDiscountProduc
                 RemainingCount = p.RemainingCount,
                 ViewCount = p.ViewCount,
                 IsActive = p.IsActive,
-                Created = p.Created.ToDateTime()
-            }).ToList()
+                Created = p.Created?.ToDateTime() ?? DateTime.MinValue
+            }).ToList() ?? new List<DiscountProductDto>()
         };
     }
 }