feat(installer): self-update pre-flight before wizard

src/ClaudeDo.Installer/App.xaml.cs

@@ -22,6 +22,104 @@ public partial class App : Application
     {
         base.OnStartup(e);
 
+        // --- Self-update pre-flight ---
+        // Resolve current exe path. Assembly.Location may point to a .dll for apphost-based
+        // .NET apps; swap to the .exe companion when that happens.
+        var currentExePath = Assembly.GetEntryAssembly()!.Location;
+        if (currentExePath.EndsWith(".dll", StringComparison.OrdinalIgnoreCase))
+        {
+            currentExePath = System.IO.Path.ChangeExtension(currentExePath, ".exe");
+        }
+
+        // Arg form: --replace-self "<old-path>"
+        var replaceSelfIndex = Array.FindIndex(e.Args, a => a.Equals("--replace-self", StringComparison.OrdinalIgnoreCase));
+        if (replaceSelfIndex >= 0 && replaceSelfIndex + 1 < e.Args.Length)
+        {
+            var oldPath = e.Args[replaceSelfIndex + 1];
+            var relaunched = await SelfUpdater.HandleReplaceSelfAsync(
+                oldPath: oldPath,
+                currentExePath: currentExePath,
+                launchProcess: path =>
+                {
+                    try
+                    {
+                        System.Diagnostics.Process.Start(new System.Diagnostics.ProcessStartInfo(path) { UseShellExecute = true });
+                        return true;
+                    }
+                    catch { return false; }
+                });
+            if (relaunched)
+            {
+                Shutdown(0);
+                return;
+            }
+            // Replacement failed — fall through to normal wizard from the temp location.
+        }
+        else
+        {
+            // Normal launch: check for a newer installer.
+            using var selfUpdateHttp = new HttpClient { Timeout = TimeSpan.FromSeconds(10) };
+            var selfUpdateReleases = new ReleaseClient(selfUpdateHttp);
+            var currentVersion = GetInstallerVersion();
+
+            var decision = await SelfUpdater.DecideUpdateAsync(selfUpdateReleases, currentVersion, CancellationToken.None);
+            if (decision.Kind == SelfUpdateDecisionKind.UpdateAvailable)
+            {
+                var prompt = new SelfUpdatePromptWindow(currentVersion, decision.LatestVersion!);
+                DarkTitleBar.Apply(prompt);
+                var ok = prompt.ShowDialog() == true;
+                if (!ok)
+                {
+                    Shutdown(0);
+                    return;
+                }
+                if (prompt.Choice == SelfUpdateChoice.Update)
+                {
+                    prompt.ShowProgress("Downloading...");
+                    var tempDir = System.IO.Path.Combine(System.IO.Path.GetTempPath(), "ClaudeDo.Installer.Update");
+                    var verifiedPath = await SelfUpdater.DownloadAndVerifyAsync(
+                        selfUpdateReleases,
+                        decision.InstallerAsset!,
+                        decision.ChecksumsAsset!,
+                        tempDir,
+                        new Progress<long>(_ => { }),
+                        CancellationToken.None);
+
+                    if (verifiedPath is null)
+                    {
+                        MessageBox.Show(prompt,
+                            "Update download or verification failed. Continuing with current installer.",
+                            "ClaudeDo Installer", MessageBoxButton.OK, MessageBoxImage.Warning);
+                    }
+                    else
+                    {
+                        try
+                        {
+                            var psi = new System.Diagnostics.ProcessStartInfo(verifiedPath)
+                            {
+                                UseShellExecute = true,
+                            };
+                            psi.ArgumentList.Add("--replace-self");
+                            psi.ArgumentList.Add(currentExePath);
+                            System.Diagnostics.Process.Start(psi);
+                            Shutdown(0);
+                            return;
+                        }
+                        catch (Exception ex)
+                        {
+                            MessageBox.Show(prompt,
+                                "Failed to launch updated installer: " + ex.Message + "\nContinuing with current installer.",
+                                "ClaudeDo Installer", MessageBoxButton.OK, MessageBoxImage.Warning);
+                        }
+                    }
+                }
+                // SelfUpdateChoice.Continue — fall through to normal wizard.
+            }
+            // No-update or check failed — fall through to normal wizard.
+        }
+
+        // --- Existing wizard start-up unchanged below this line ---
+
         _services = BuildServices();
 
         var context = _services.GetRequiredService<InstallContext>();

src/ClaudeDo.Installer/Views/SelfUpdatePromptWindow.xaml

@@ -0,0 +1,25 @@
+<Window x:Class="ClaudeDo.Installer.Views.SelfUpdatePromptWindow"
+        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
+        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+        Title="ClaudeDo Installer Update"
+        Width="460" Height="200"
+        WindowStartupLocation="CenterScreen"
+        ResizeMode="NoResize"
+        Background="#1a1a1a" Foreground="#f0f0f0">
+    <Grid Margin="20">
+        <Grid.RowDefinitions>
+            <RowDefinition Height="Auto"/>
+            <RowDefinition Height="Auto"/>
+            <RowDefinition Height="*"/>
+            <RowDefinition Height="Auto"/>
+        </Grid.RowDefinitions>
+        <TextBlock Grid.Row="0" FontSize="16" FontWeight="SemiBold" Text="A newer installer is available"/>
+        <TextBlock Grid.Row="1" Margin="0,8,0,0" TextWrapping="Wrap" x:Name="DetailText"/>
+        <TextBlock Grid.Row="2" Margin="0,12,0,0" TextWrapping="Wrap" Foreground="#a0a0a0" x:Name="ProgressText" Visibility="Collapsed"/>
+        <StackPanel Grid.Row="3" Orientation="Horizontal" HorizontalAlignment="Right">
+            <Button x:Name="UpdateBtn" Content="Update" MinWidth="90" Margin="4,0" Padding="10,4" Click="UpdateBtn_Click" IsDefault="True"/>
+            <Button x:Name="ContinueBtn" Content="Continue anyway" MinWidth="140" Margin="4,0" Padding="10,4" Click="ContinueBtn_Click"/>
+            <Button x:Name="CancelBtn" Content="Cancel" MinWidth="90" Margin="4,0" Padding="10,4" Click="CancelBtn_Click" IsCancel="True"/>
+        </StackPanel>
+    </Grid>
+</Window>

src/ClaudeDo.Installer/Views/SelfUpdatePromptWindow.xaml.cs

@@ -0,0 +1,42 @@
+using System.Windows;
+
+namespace ClaudeDo.Installer.Views;
+
+public enum SelfUpdateChoice { Update, Continue, Cancel }
+
+public partial class SelfUpdatePromptWindow : Window
+{
+    public SelfUpdateChoice Choice { get; private set; } = SelfUpdateChoice.Cancel;
+
+    public SelfUpdatePromptWindow(string currentVersion, string latestVersion)
+    {
+        InitializeComponent();
+        DetailText.Text = $"Installer v{latestVersion} is available (you are running v{currentVersion}). Update before continuing?";
+    }
+
+    public void ShowProgress(string text)
+    {
+        ProgressText.Text = text;
+        ProgressText.Visibility = Visibility.Visible;
+        UpdateBtn.IsEnabled = false;
+        ContinueBtn.IsEnabled = false;
+    }
+
+    private void UpdateBtn_Click(object sender, RoutedEventArgs e)
+    {
+        Choice = SelfUpdateChoice.Update;
+        DialogResult = true;
+    }
+
+    private void ContinueBtn_Click(object sender, RoutedEventArgs e)
+    {
+        Choice = SelfUpdateChoice.Continue;
+        DialogResult = true;
+    }
+
+    private void CancelBtn_Click(object sender, RoutedEventArgs e)
+    {
+        Choice = SelfUpdateChoice.Cancel;
+        DialogResult = false;
+    }
+}