Fix: exceptions not printing in Output window.

Author: rezanid

src/Tests/XrmTools.Tests/Logging/OutputLoggerTests.cs

@@ -0,0 +1,20 @@
+namespace XrmTools.Tests.Logging;
+using System;
+using FluentAssertions;
+using Xunit;
+using XrmTools.Logging.Compatibility;
+
+public class OutputLoggerTests
+{
+    [Fact]
+    public void AppendException_Should_Include_Exception_Details()
+    {
+        var logRecord = "[Error] TestCategory: Failed to register plugin assembly.";
+        var exception = new InvalidOperationException("Boom");
+
+        var result = OutputLogger.AppendException(logRecord, exception);
+
+        result.Should().StartWith(logRecord + Environment.NewLine);
+        result.Should().Contain(exception.ToString());
+    }
+}

src/XrmTools/Logging/OutputLogger.cs

@@ -46,12 +46,19 @@ public void Log<TState>(LogLevel logLevel, EventId eventId, TState state, Except
             logRecord = $"{string.Join(" => ", scopeInfo)}: {logRecord}";
         }
 
-        if (exception != null && logLevel <= LogLevel.Debug)
+        logRecord = AppendException(logRecord, exception);
+
+        outputLoggerService.OutputString(logRecord + Environment.NewLine);
+    }
+
+    internal static string AppendException(string logRecord, Exception? exception)
+    {
+        if (exception is null)
         {
-            logRecord += Environment.NewLine + exception.ToString();
+            return logRecord;
         }
 
-        outputLoggerService.OutputString(logRecord + Environment.NewLine);
+        return logRecord + Environment.NewLine + exception;
     }
 
     private class Scope(object state) : IDisposable

src/XrmTools/Services/PluginRegistrationService.cs

@@ -395,7 +395,7 @@ public async Task<PluginRegistrationResult> RegisterAsync(RegistrationInput inpu
             catch (Exception ex)    
             {
                 _log.LogError(ex, "An error occurred while registering steps/custom APIs after package upload.");
-                return PluginRegistrationResult.Failure("Plugin registration failed during follow-up registration of steps/custom APIs.");
+                return PluginRegistrationResult.Failure("Plugin registration failed during follow-up registration of steps/custom APIs. Please check the Output window for more details.");
             }
         }