Do not show CmdPal on startup (#38027)

Adds a command line arg to not show CmdPal on startup. When starting from PT Run, we won't immediately show the window. 

as noted in #37908

src/modules/cmdpal/Microsoft.CmdPal.UI/MainWindow.xaml.cs

@@ -466,6 +466,8 @@ public sealed partial class MainWindow : Window,
                         // so that we can bind hotkeys to individual commands
                         if (!this.Visible || !isRootHotkey)
                         {
+                            Activate();
+
                             Summon(hotkey.CommandId);
                         }
                         else if (isRootHotkey)