Display output dialog content in tabs

src/Beutl.Extensibility/OutputExtension.cs

@@ -15,6 +15,8 @@ public interface IOutputContext : IDisposable, IJsonSerializable
 
     string TargetFile { get; }
 
+    IReactiveProperty<string> Name { get; }
+
     IReadOnlyReactiveProperty<bool> IsIndeterminate { get; }
 
     IReadOnlyReactiveProperty<bool> IsEncoding { get; }

src/Beutl/Services/EditorService.cs

@@ -113,7 +113,6 @@ public void ActivateTabItem(string? file)
 
                 if (ext?.TryCreateContext(file, out IEditorContext? context) == true)
                 {
-                    context.IsEnabled.Value = !OutputService.Current.Items.Any(x => x.Context.TargetFile == file && x.Context.IsEncoding.Value);
                     var tabItem2 = new EditorTabItem(context)
                     {
                         IsSelected =