Merge more UI refactor stuff (#11277)

* Changelog+options ui controller
* Sandbox UI controller
* Escape menu UI controller

Content.Client/UserInterface/Systems/Sandbox/Windows/SandboxWindow.xaml.cs

@@ -0,0 +1,14 @@
+using Robust.Client.AutoGenerated;
+using Robust.Client.UserInterface.CustomControls;
+using Robust.Client.UserInterface.XAML;
+
+namespace Content.Client.UserInterface.Systems.Sandbox.Windows;
+
+[GenerateTypedNameReferences]
+public sealed partial class SandboxWindow : DefaultWindow
+{
+    public SandboxWindow()
+    {
+        RobustXamlLoader.Load(this);
+    }
+}