Handle debug-step Enter before tree items consume it

TreeViewItem handles Enter for expand and collapse before bubble-phase handlers run, so install the replay shortcut in the tunnel phase to keep group-row commands reachable.

Assisted-by: OpenCode:openai/gpt-5.5:OpenCode

ILSpy/Views/DebugSteps.axaml

@@ -45,7 +45,6 @@
 		          ItemsSource="{Binding Steps}"
 		          SelectedItem="{Binding SelectedStep, Mode=TwoWay}"
 		          DoubleTapped="OnTreeDoubleTapped"
-		          KeyDown="OnTreeKeyDown"
 		          x:CompileBindings="False">
 			<TreeView.Styles>
 				<!-- Hide rows that neither match the filter nor lead to a match, and expand the tree

ILSpy/Views/DebugSteps.axaml.cs

@@ -37,6 +37,11 @@ namespace ICSharpCode.ILSpy.Views
 		public DebugSteps()
 		{
 			InitializeComponent();
+			// TreeViewItem.OnKeyDown consumes Enter/Return to expand or collapse the focused row
+			// (marking the event handled) before it bubbles, so a bubble-phase handler never sees
+			// Enter on a group row. Intercept in the tunnel phase, ahead of the item, so Enter and
+			// Shift+Enter drive the show-state commands for both leaf and group steps.
+			StepsTree.AddHandler(InputElement.KeyDownEvent, OnTreeKeyDown, RoutingStrategies.Tunnel, handledEventsToo: true);
 		}
 
 		void OnTreeDoubleTapped(object? sender, TappedEventArgs e)