feat(docking): add DockDocument and DockGroup

src/Editor/Ghost.Editor/View/Controls/Docking/DockGroup.cs

@@ -0,0 +1,47 @@
+using Microsoft.UI.Xaml;
+using Microsoft.UI.Xaml.Controls;
+
+namespace Ghost.Editor.View.Controls.Docking;
+
+[TemplatePart(Name = "PART_TabView", Type = typeof(TabView))]
+public class DockGroup : DockContainer
+{
+    private TabView? _tabView;
+
+    public DockGroup()
+    {
+        DefaultStyleKey = typeof(DockGroup);
+    }
+
+    protected override void OnApplyTemplate()
+    {
+        base.OnApplyTemplate();
+        _tabView = GetTemplateChild("PART_TabView") as TabView;
+        UpdateTabs();
+    }
+
+    protected override void OnChildrenUpdated()
+    {
+        UpdateTabs();
+    }
+
+    private void UpdateTabs()
+    {
+        if (_tabView == null) return;
+
+        _tabView.TabItems.Clear();
+        foreach (var child in Children)
+        {
+            if (child is DockDocument doc)
+            {
+                var tabItem = new TabViewItem
+                {
+                    Header = doc.Title,
+                    Content = doc.Content,
+                    Tag = doc
+                };
+                _tabView.TabItems.Add(tabItem);
+            }
+        }
+    }
+}