Complete migration: fix console markup and circular reference issues

Co-authored-by: christianhelle <[email protected]>

Author: Copilot

src/CurlGenerator.Core/ScriptFileGenerator.cs

@@ -237,7 +237,19 @@ private static void TryLog(string message)
 
     private static string SerializeObject(object obj)
     {
-        return Newtonsoft.Json.JsonConvert.SerializeObject(obj, Newtonsoft.Json.Formatting.Indented);
+        try
+        {
+            var settings = new Newtonsoft.Json.JsonSerializerSettings
+            {
+                ReferenceLoopHandling = Newtonsoft.Json.ReferenceLoopHandling.Ignore,
+                Formatting = Newtonsoft.Json.Formatting.Indented
+            };
+            return Newtonsoft.Json.JsonConvert.SerializeObject(obj, settings);
+        }
+        catch
+        {
+            return obj?.ToString() ?? "null";
+        }
     }
 
     private static string GenerateSampleJsonFromSchema(OpenApiSchema? schema)

src/CurlGenerator/GenerateCommand.cs

@@ -55,23 +55,27 @@ public override async Task<int> ExecuteAsync(CommandContext context, Settings se
         }
         catch (OpenApiUnsupportedSpecVersionException exception)
         {
-            AnsiConsole.MarkupLine($"{Crlf}[red]Error:{Crlf}{exception.Message}[/]");
+            var escapedMessage = exception.Message.Replace("[", "[[").Replace("]", "]]");
+            AnsiConsole.MarkupLine($"{Crlf}[red]Error:{Crlf}{escapedMessage}[/]");
             AnsiConsole.MarkupLine(
                 $"{Crlf}[yellow]Tips:{Crlf}" +
                 $"Consider using the --skip-validation argument.{Crlf}" +
                 $"In some cases, the features that are specific to the " +
                 $"unsupported versions of OpenAPI specifications aren't really used.{Crlf}" +
-                $"This tool uses NSwag libraries to parse the OpenAPI document and " +
-                $"Microsoft.OpenApi libraries for validation.{Crlf}{Crlf}[/]");
+                $"This tool uses Microsoft.OpenApi libraries for both parsing and validation.{Crlf}{Crlf}[/]");
             return exception.HResult;
         }
         catch (Exception exception)
         {
             if (exception is not OpenApiValidationException)
             {
-                AnsiConsole.MarkupLine($"{Crlf}[red]Error:{Crlf}{exception.Message}[/]");
+                // Escape markup characters in exception messages
+                var escapedMessage = exception.Message.Replace("[", "[[").Replace("]", "]]");
+                var escapedStackTrace = exception.StackTrace?.Replace("[", "[[").Replace("]", "]]") ?? "";
+                
+                AnsiConsole.MarkupLine($"{Crlf}[red]Error:{Crlf}{escapedMessage}[/]");
                 AnsiConsole.MarkupLine($"[red]Exception:{Crlf}{exception.GetType()}[/]");
-                AnsiConsole.MarkupLine($"[yellow]Stack Trace:{Crlf}{exception.StackTrace}[/]");
+                AnsiConsole.MarkupLine($"[yellow]Stack Trace:{Crlf}{escapedStackTrace}[/]");
             }
 
             await Analytics.LogError(exception, settings);
@@ -104,7 +108,8 @@ private static async Task AcquireAzureEntraIdToken(Settings settings)
         }
         catch (Exception exception)
         {
-            AnsiConsole.MarkupLine($"{Crlf}[red]Error:{Crlf}{exception.Message}[/]");
+            var escapedMessage = exception.Message.Replace("[", "[[").Replace("]", "]]");
+            AnsiConsole.MarkupLine($"{Crlf}[red]Error:{Crlf}{escapedMessage}[/]");
         }
     }
 
@@ -158,7 +163,9 @@ private static void TryWriteLine(
     {
         try
         {
-            AnsiConsole.MarkupLine($"[{color}]{label}:{Crlf}{error}{Crlf}[/]");
+            // Escape markup characters in the error message to prevent markup interpretation
+            var escapedError = error.ToString().Replace("[", "[[").Replace("]", "]]");
+            AnsiConsole.MarkupLine($"[{color}]{label}:{Crlf}{escapedError}{Crlf}[/]");
         }
         catch
         {
@@ -253,7 +260,9 @@ private static void DisplayResults(GeneratorResult result, TimeSpan elapsed, Set
                     < 1024 * 1024 => $"{fileSize / 1024.0:F1} KB",
                     _ => $"{fileSize / (1024.0 * 1024.0):F1} MB"
                 };
-                AnsiConsole.MarkupLine($"  📝 [cyan]{file.Filename}[/] [dim]({fileSizeText})[/]");
+                // Escape markup characters in filename
+                var escapedFilename = file.Filename.Replace("[", "[[").Replace("]", "]]");
+                AnsiConsole.MarkupLine($"  📝 [cyan]{escapedFilename}[/] [dim]({fileSizeText})[/]");
             }
         }
         else