style(demos): file-scoped namespace + reindent DemoPickable

Disp/DemoPickable.cs

@@ -2,19 +2,19 @@
 using Hi.Geom;
 using System;
 
-namespace Sample.Disp
+namespace Sample.Disp;
+
+/// <summary>
+/// Demonstrates creation of pickable 3D geometry at the primitive level.
+/// Shows how to assign picking IDs directly to geometry vertices and create interactive triangles.
+/// Uses a lower-level approach than the Pickable base class for more precise control.
+/// </summary>
+/// <remarks>
+/// ### Source Code
+/// [!code-csharp[SampleCode](~/../Hi.Sample.Wpf/Disp/DemoPickable.cs)]
+/// </remarks>
+public class DemoPickable : IDisplayee
 {
-    /// <summary>
-    /// Demonstrates creation of pickable 3D geometry at the primitive level.
-    /// Shows how to assign picking IDs directly to geometry vertices and create interactive triangles.
-    /// Uses a lower-level approach than the Pickable base class for more precise control.
-    /// </summary>
-    /// <remarks>
-    /// ### Source Code
-    /// [!code-csharp[SampleCode](~/../Hi.Sample.Wpf/Disp/DemoPickable.cs)]
-    /// </remarks>
-    public class DemoPickable : IDisplayee
-	{
 	private readonly Drawing draw;
 	private readonly ShowEventPickable pickable;
 
@@ -55,7 +55,4 @@ namespace Sample.Disp
 	{
 		DemoUtil.RunApplication("DemoPickable", new DemoPickable());
 	}
-	}
-
-
 }