Add parameterless entity test

tests/AggregateKit.Tests/EntityTests.cs

@@ -245,12 +245,21 @@ public void Entity_Parameterless_Constructor_Works_For_EF_Core()
             // This test ensures the parameterless constructor works (needed for EF Core)
             // We can't directly test it since it's protected, but we can verify it exists
             // by checking that the type can be instantiated through reflection
-            
+
             var entityType = typeof(TestEntity);
             var constructors = entityType.GetConstructors(System.Reflection.BindingFlags.NonPublic | System.Reflection.BindingFlags.Instance);
             var parameterlessConstructor = Array.Find(constructors, c => c.GetParameters().Length == 0);
-            
+
             Assert.NotNull(parameterlessConstructor);
         }
+
+        [Fact]
+        public void Entity_ParameterlessConstructor_CanInstantiate()
+        {
+            var entity = new ParameterlessEntity();
+
+            Assert.NotNull(entity);
+            Assert.Equal(default(Guid), entity.Id);
+        }
     }
-} 
+}

tests/AggregateKit.Tests/ParameterlessEntity.cs

@@ -0,0 +1,12 @@
+using System;
+
+namespace AggregateKit.Tests
+{
+    public class ParameterlessEntity : Entity<Guid>
+    {
+        public ParameterlessEntity() : base()
+        {
+        }
+    }
+}
+