chore: use file-scoped namespace

src/Shared/HandyControl_Shared/Controls/Screenshot/Screenshot.cs

@@ -2,14 +2,13 @@
 using System.Windows.Media;
 using HandyControl.Data;
 
-namespace HandyControl.Controls
+namespace HandyControl.Controls;
+
+public class Screenshot
 {
-    public class Screenshot
-    {
-        public static event EventHandler<FunctionEventArgs<ImageSource>> Snapped;
+    public static event EventHandler<FunctionEventArgs<ImageSource>> Snapped;
 
-        public void Start() => new ScreenshotWindow(this).Show();
+    public void Start() => new ScreenshotWindow(this).Show();
 
-        internal void OnSnapped(ImageSource source) => Snapped?.Invoke(this, new FunctionEventArgs<ImageSource>(source));
-    }
-}
+    internal void OnSnapped(ImageSource source) => Snapped?.Invoke(this, new FunctionEventArgs<ImageSource>(source));
+}