feat(app): register UpdateCheckService and InstallerLocator in DI

src/ClaudeDo.App/Program.cs

@@ -1,6 +1,7 @@
 using Avalonia;
 using ClaudeDo.Data;
 using ClaudeDo.Data.Git;
+using ClaudeDo.Releases;
 using ClaudeDo.Ui;
 using ClaudeDo.Ui.Services;
 using ClaudeDo.Ui.ViewModels;
@@ -9,6 +10,8 @@ using ClaudeDo.Ui.ViewModels.Modals;
 using Microsoft.EntityFrameworkCore;
 using Microsoft.Extensions.DependencyInjection;
 using System;
+using System.Net.Http;
+using System.Reflection;
 using System.Runtime.InteropServices;
 
 namespace ClaudeDo.App;
@@ -75,6 +78,17 @@ sealed class Program
         sc.AddSingleton<GitService>();
         sc.AddSingleton(sp => new WorkerClient(sp.GetRequiredService<AppSettings>().SignalRUrl));
 
+        // Release check + installer update
+        sc.AddSingleton<HttpClient>(_ => new HttpClient { Timeout = TimeSpan.FromSeconds(10) });
+        sc.AddSingleton<IReleaseClient>(sp => new ReleaseClient(sp.GetRequiredService<HttpClient>()));
+        sc.AddSingleton<InstallerLocator>();
+        sc.AddSingleton(sp =>
+        {
+            var releases = sp.GetRequiredService<IReleaseClient>();
+            var version = Assembly.GetEntryAssembly()?.GetName().Version?.ToString() ?? "0.0.0.0";
+            return new UpdateCheckService(releases, version);
+        });
+
         // ViewModels
         sc.AddTransient<WorktreeModalViewModel>();
         sc.AddTransient<SettingsModalViewModel>();

src/ClaudeDo.Ui/ViewModels/IslandsShellViewModel.cs

@@ -19,6 +19,9 @@ public sealed partial class IslandsShellViewModel : ViewModelBase
 
     public bool IsOffline => !Worker.IsConnected && !Worker.IsReconnecting;
 
+    private readonly UpdateCheckService _updateCheck;
+    private readonly InstallerLocator _installerLocator;
+
     [ObservableProperty]
     private double _windowWidth = 1280;
 
@@ -47,9 +50,13 @@ public sealed partial class IslandsShellViewModel : ViewModelBase
         ListsIslandViewModel lists,
         TasksIslandViewModel tasks,
         DetailsIslandViewModel details,
-        WorkerClient worker)
+        WorkerClient worker,
+        UpdateCheckService updateCheck,
+        InstallerLocator installerLocator)
     {
         Lists = lists; Tasks = tasks; Details = details; Worker = worker;
+        _updateCheck = updateCheck;
+        _installerLocator = installerLocator;
         Lists.SelectionChanged += (_, _) => Tasks.LoadForList(Lists.SelectedList);
         Tasks.SelectionChanged += (_, _) => Details.Bind(Tasks.SelectedTask);
         Tasks.TasksChanged     += (_, _) => _ = Lists.RefreshCountsAsync();