fixed GSA writing, added always-edit button and search in file and for file

GsaEditor/Views/MainWindow.axaml.cs

@@ -59,6 +59,19 @@ public partial class MainWindow : Window
         {
             ApplySyntaxHighlighting(vm);
         }
+
+        if (e.PropertyName == nameof(MainWindowViewModel.SelectedNode))
+        {
+            // Reflect programmatic selection (e.g. from search results) in the tree.
+            // Posted so newly expanded parent containers are realized first.
+            var tree = this.FindControl<TreeView>("ArchiveTree");
+            if (tree != null && vm.SelectedNode != null && !ReferenceEquals(tree.SelectedItem, vm.SelectedNode))
+            {
+                Avalonia.Threading.Dispatcher.UIThread.Post(
+                    () => tree.SelectedItem = vm.SelectedNode,
+                    Avalonia.Threading.DispatcherPriority.Background);
+            }
+        }
     }
 
     private void ApplySyntaxHighlighting(MainWindowViewModel vm)