TASK 48 slice 3: the self-updater is deleted - the Store updates the app

The creator's ruling (2026-09-27) is Store MSIX + Store IAP, so Microsoft delivers
the updates and the in-app updater is gone rather than parked. This is a
COMPLIANCE action, not cleanup: the Velopack bootstrap downloaded and executed a
payload, which Store policy 10.2.2 does not permit.

Three edit sites, as planned: the PackageReference in ytLive.csproj, 'using
Velopack;' in App.xaml.cs, and the bootstrap block. The self-hosted DigitalOcean
update-URL droplet dies with it.

Guard: ytLive.Tests/StorePackagingTests.cs - the ONE test asserts the app project
references no updater package (Velopack/Squirrel/NetSparkle/AutoUpdater/WinSparkle)
and that no app source file uses the updater API. The check matches CODE (a using
directive, a type usage), not a bare word, so a file's prose may still name what it
deliberately does not do.

Smoke-tested after the removal: MainWindow loaded, 0 exceptions in startup.log.
Full suite 437/437, 0 warnings.

App.xaml.cs

@@ -1,6 +1,5 @@
 using System.Windows;
 using System.Windows.Threading;
-using Velopack;
 using ytLive.Helpers;
 
 namespace ytLive;
@@ -31,19 +30,8 @@ public partial class App : Application
         // the per-build GUID is forensic only and lands here.
         AppLog.Write($"Build {ytLive.Helpers.BuildStamp.Id} (compiled {ytLive.Helpers.BuildStamp.BuiltLocal})");
 
-        // Velopack auto-update bootstrap — checks for updates on startup and
-        // applies them (the app restarts automatically if an update is found).
-        // Update URL is configured per-deployment (self-hosted on DO droplet);
-        // when no URL is set, the check is a no-op.
-        try
-        {
-            VelopackApp.Build()
-                .Run();
-        }
-        catch (Exception ex)
-        {
-            AppLog.Write($"Velopack bootstrap failed (non-fatal): {ex.Message}");
-        }
+        // There is deliberately NO self-update bootstrap here: the Microsoft Store updates the
+        // app (TASK 48 — Store MSIX route), and a second updater would fight it.
 
         base.OnStartup(e);
         AppLog.Write("App OnStartup end");