Add Explorer Workbench with hierarchical, off-UI Storage analysis.

Storage queries run in the background with cancellation and covering indexes so switching views no longer freezes the UI.

Co-authored-by: Cursor <cursoragent@cursor.com>

src/Explorer.App/App.xaml.cs

@@ -0,0 +1,56 @@
+using System.IO;
+using System.Windows;
+using Explorer.Presentation.ViewModels;
+using Microsoft.Extensions.DependencyInjection;
+using Microsoft.Extensions.Hosting;
+using Serilog;
+
+namespace Explorer.App;
+
+public partial class App : System.Windows.Application
+{
+    private IHost? _host;
+
+    protected override async void OnStartup(StartupEventArgs e)
+    {
+        base.OnStartup(e);
+        DispatcherUnhandledException += (_, args) =>
+        {
+            Log.Error(args.Exception, "Unhandled UI exception");
+            args.Handled = true;
+        };
+
+        var env = new Windows.WindowsAppEnvironment();
+        Log.Logger = new LoggerConfiguration()
+            .MinimumLevel.Information()
+            .WriteTo.File(
+                Path.Combine(env.LogDirectory, "explorer-.log"),
+                rollingInterval: RollingInterval.Day,
+                retainedFileCountLimit: 14)
+            .CreateLogger();
+
+        _host = Host.CreateDefaultBuilder()
+            .UseSerilog()
+            .ConfigureServices((_, services) => services.AddExplorer())
+            .Build();
+
+        var vm = _host.Services.GetRequiredService<MainViewModel>();
+        await vm.InitializeAsync().ConfigureAwait(true);
+        await _host.StartAsync().ConfigureAwait(true);
+        var window = _host.Services.GetRequiredService<MainWindow>();
+        window.DataContext = vm;
+        window.Show();
+    }
+
+    protected override async void OnExit(ExitEventArgs e)
+    {
+        if (_host is not null)
+        {
+            await _host.StopAsync(TimeSpan.FromSeconds(3)).ConfigureAwait(true);
+            _host.Dispose();
+        }
+
+        Log.CloseAndFlush();
+        base.OnExit(e);
+    }
+}