feat(installer): mode-aware wizard page list + Update-mode step pipeline

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/ClaudeDo.Installer/Pages/InstallPage/InstallPageViewModel.cs

@@ -3,15 +3,17 @@ using System.Diagnostics;
 using System.Windows;
 using System.Windows.Controls;
 using ClaudeDo.Installer.Core;
+using ClaudeDo.Installer.Steps;
 using CommunityToolkit.Mvvm.ComponentModel;
 using CommunityToolkit.Mvvm.Input;
+using Microsoft.Extensions.DependencyInjection;
 
 namespace ClaudeDo.Installer.Pages.InstallPage;
 
 public partial class InstallPageViewModel : ObservableObject, IInstallerPage
 {
     private readonly InstallContext _context;
-    private readonly InstallerService _installerService;
+    private readonly IServiceProvider _serviceProvider;
     private InstallPageView? _view;
     private CancellationTokenSource? _cts;
 
@@ -29,22 +31,31 @@ public partial class InstallPageViewModel : ObservableObject, IInstallerPage
     [ObservableProperty] private bool _hasErrors;
     [ObservableProperty] private double _overallProgress;
 
-    public InstallPageViewModel(InstallContext context, InstallerService installerService)
+    public InstallPageViewModel(InstallContext context, IServiceProvider serviceProvider)
     {
         _context = context;
-        _installerService = installerService;
+        _serviceProvider = serviceProvider;
     }
 
     public Task LoadAsync()
     {
         Steps.Clear();
-        Steps.Add(new StepViewModel("Publish ClaudeDo.App"));
+        if (_context.Mode == InstallerMode.Update)
-        Steps.Add(new StepViewModel("Publish ClaudeDo.Worker"));
+        {
-        Steps.Add(new StepViewModel("Deploy Binaries"));
+            Steps.Add(new StepViewModel("Stop Worker Service"));
+            Steps.Add(new StepViewModel("Download and Extract"));
+            Steps.Add(new StepViewModel("Start Worker Service"));
+            Steps.Add(new StepViewModel("Write Install Manifest"));
+        }
+        else
+        {
+            Steps.Add(new StepViewModel("Download and Extract"));
             Steps.Add(new StepViewModel("Write Configuration"));
             Steps.Add(new StepViewModel("Initialize Database"));
             Steps.Add(new StepViewModel("Register Windows Service"));
             Steps.Add(new StepViewModel("Create Shortcuts"));
+            Steps.Add(new StepViewModel("Write Install Manifest"));
+        }
         return Task.CompletedTask;
     }
 
@@ -85,7 +96,24 @@ public partial class InstallPageViewModel : ObservableObject, IInstallerPage
 
         try
         {
-            var results = await _installerService.ExecuteAsync(_context, progress, _cts.Token);
+            IEnumerable<IInstallStep> steps;
+            if (_context.Mode == InstallerMode.Update)
+            {
+                steps = new IInstallStep[]
+                {
+                    _serviceProvider.GetRequiredService<StopServiceStep>(),
+                    _serviceProvider.GetRequiredService<DownloadAndExtractStep>(),
+                    _serviceProvider.GetRequiredService<StartServiceStep>(),
+                    _serviceProvider.GetRequiredService<WriteInstallManifestStep>(),
+                };
+            }
+            else
+            {
+                steps = _serviceProvider.GetServices<IInstallStep>();
+            }
+
+            var runner = new InstallerService(steps);
+            var results = await runner.ExecuteAsync(_context, progress, _cts.Token);
             HasErrors = results.Any(r => !r.Result.Success);
         }
         catch (OperationCanceledException)

src/ClaudeDo.Installer/Views/WizardViewModel.cs

@@ -1,5 +1,8 @@
+using System.Linq;
 using System.Windows;
 using ClaudeDo.Installer.Core;
+using ClaudeDo.Installer.Pages.InstallPage;
+using ClaudeDo.Installer.Pages.WelcomePage;
 using CommunityToolkit.Mvvm.ComponentModel;
 using CommunityToolkit.Mvvm.Input;
 
@@ -28,9 +31,14 @@ public partial class WizardViewModel : ObservableObject
 
     public WizardViewModel(PageResolver resolver, InstallContext context)
     {
-        Pages = resolver.WizardPages;
         _context = context;
 
+        var all = resolver.WizardPages;
+        Pages = context.Mode == InstallerMode.Update
+            ? all.Where(p => p is WelcomePageViewModel
+                          || p is InstallPageViewModel).ToList()
+            : all;
+
         if (Pages.Count > 0)
             _ = InitAsync();
     }