fix: make ThrowOnPipelineFailure configurable via PipelineOptions

Add ThrowOnPipelineFailure option (default true) to control whether
PipelineFailedException is thrown when pipeline fails. This ensures:

- Production/CI: Throws by default for non-zero exit codes
- Tests: Can disable to inspect PipelineSummary without catching exceptions

Test helper now sets ThrowOnPipelineFailure = false by default so existing
tests continue to work as expected.

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

Author: thomhurst

src/ModularPipelines/Engine/Executors/ExecutionOrchestrator.cs

@@ -1,10 +1,12 @@
 using System.Diagnostics;
 using Microsoft.Extensions.Logging;
+using Microsoft.Extensions.Options;
 using ModularPipelines.Enums;
 using ModularPipelines.Exceptions;
 using ModularPipelines.Helpers;
 using ModularPipelines.Models;
 using ModularPipelines.Modules;
+using ModularPipelines.Options;
 
 namespace ModularPipelines.Engine.Executors;
 
@@ -34,6 +36,7 @@ internal class ExecutionOrchestrator : IExecutionOrchestrator
     private readonly EngineCancellationToken _engineCancellationToken;
     private readonly IThreadPoolConfigurator _threadPoolConfigurator;
     private readonly IExceptionRethrowService _exceptionRethrowService;
+    private readonly IOptions<PipelineOptions> _options;
     private readonly ILogger<ExecutionOrchestrator> _logger;
 
     private readonly object _lock = new();
@@ -50,6 +53,7 @@ public ExecutionOrchestrator(
         EngineCancellationToken engineCancellationToken,
         IThreadPoolConfigurator threadPoolConfigurator,
         IExceptionRethrowService exceptionRethrowService,
+        IOptions<PipelineOptions> options,
         ILogger<ExecutionOrchestrator> logger)
     {
         _pipelineInitializer = pipelineInitializer;
@@ -61,6 +65,7 @@ public ExecutionOrchestrator(
         _engineCancellationToken = engineCancellationToken;
         _threadPoolConfigurator = threadPoolConfigurator;
         _exceptionRethrowService = exceptionRethrowService;
+        _options = options;
         _logger = logger;
     }
 
@@ -149,7 +154,7 @@ private async Task<PipelineSummary> OnEnd(OrganizedModules organizedModules, Sto
         }
 
         // Throw exception if pipeline failed - this ensures non-zero exit code in CI
-        if (pipelineSummary.Status == Status.Failed)
+        if (pipelineSummary.Status == Status.Failed && _options.Value.ThrowOnPipelineFailure)
         {
             var failedModules = pipelineSummary.GetFailedModuleResults()
                 .Select(r => r.ModuleName)

src/ModularPipelines/Options/PipelineOptions.cs

@@ -205,4 +205,21 @@ public bool ShowProgressInConsole
     /// </para>
     /// </remarks>
     public CommandExecutionOptions? DefaultExecutionOptions { get; set; }
+
+    /// <summary>
+    /// Gets or sets a value indicating whether to throw a <see cref="Exceptions.PipelineFailedException"/>
+    /// when the pipeline completes with one or more failed modules.
+    /// </summary>
+    /// <remarks>
+    /// <para>
+    /// Default is <c>true</c> to ensure non-zero exit codes in CI/CD environments.
+    /// When a pipeline fails, the exception is thrown after the summary has been printed,
+    /// ensuring users see the full output before the process exits.
+    /// </para>
+    /// <para>
+    /// Set to <c>false</c> for scenarios where you want to inspect the <see cref="Models.PipelineSummary"/>
+    /// programmatically without catching exceptions (e.g., in tests or when implementing custom failure handling).
+    /// </para>
+    /// </remarks>
+    public bool ThrowOnPipelineFailure { get; set; } = true;
 }

test/ModularPipelines.TestHelpers/TestPipelineHostBuilder.cs

@@ -29,6 +29,7 @@ public static PipelineBuilder Create(TestHostSettings testHostSettings, TimeProv
         builder.Options.PrintResults = false;
         builder.Options.PrintLogo = false;
         builder.Options.PrintDependencyChains = false;
+        builder.Options.ThrowOnPipelineFailure = false; // Tests handle failures explicitly
 
         if (testHostSettings.ClearLogProviders)
         {