minimal improvements for ApiResponse

Pilz.Net/Api/ApiException.cs

@@ -0,0 +1,16 @@
+namespace Pilz.Net.Api;
+
+public class ApiException : Exception
+{
+    public ApiException()
+    {
+    }
+
+    public ApiException(string? message) : base(message)
+    {
+    }
+
+    public ApiException(string? message, Exception? innerException) : base(message, innerException)
+    {
+    }
+}

Pilz.Net/Api/ApiResponse.cs

@@ -10,6 +10,6 @@ public record class ApiResponse(
     public void EnsureOk()
     {
         if (!IsOk)
-            throw new Exception("Api return is not ok!");
+            throw new ApiException("Api return is not ok: " + StatusCode);
     }
 }

Pilz.Net/Api/ApiResponse{T}.cs

@@ -12,9 +12,10 @@ public record class ApiResponse<T>(
     public bool IsOk => StatusCode == HttpStatusCode.OK && Message is not null;
 
     [MemberNotNull(nameof(Message))]
-    public void EnsureOk()
+    public T EnsureOk()
     {
         if (!IsOk)
-            throw new Exception("Api return is not ok!");
+            throw new ApiException("Api return is not ok: " + StatusCode);
+        return Message;
     }
 }