Fix broadcast view forcing always-on-top over main tracker window (#21)

Show BroadcastView without an owner window. Passing mainWindow as the
owner to Show() causes the OS to enforce that the owned window always
stays above its owner in z-order, making the broadcast view impossible
to hide behind the tracker. Showing it as an independent top-level
window restores the expected behaviour.

Fixes #18

Co-authored-by: EmoSaru <emosaru@emosaru.com>
Co-authored-by: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: 3 people

EmoTracker/ApplicationModel.cs

@@ -199,10 +199,10 @@ private void ShowBroadcastView(object obj)
                 mBroadcastView = new BroadcastView();
                 mBroadcastView.Closing += (_, _) => mBroadcastView = null;
 
-                var mainWindow = (Avalonia.Application.Current?.ApplicationLifetime
-                    as Avalonia.Controls.ApplicationLifetimes.IClassicDesktopStyleApplicationLifetime)?.MainWindow;
-
-                mBroadcastView.Show(mainWindow);
+                // Show without an owner so the broadcast view is an independent
+                // top-level window.  Passing the main window as owner causes the
+                // OS to force the broadcast view above the main window at all times.
+                mBroadcastView.Show();
             }
             else
             {