feat: initial ElasticWrapPanel.

src/Ursa/Controls/ElasticWrapPanel.cs

@@ -0,0 +1,33 @@
+using Avalonia;
+using Avalonia.Controls;
+
+namespace Ursa.Controls;
+
+public class ElasticWrapPanel : Panel
+{
+    protected override Size MeasureOverride(Size availableSize)
+    {
+        var panelDesiredSize = new Size();
+
+        foreach (var child in Children)
+        {
+            child.Measure(availableSize);
+            panelDesiredSize = child.DesiredSize;
+        }
+
+        return panelDesiredSize;
+    }
+
+    protected override Size ArrangeOverride(Size finalSize)
+    {
+        foreach (var child in Children)
+        {
+            const double x = 50;
+            const double y = 50;
+
+            child.Arrange(new Rect(new Point(x, y), child.DesiredSize));
+        }
+
+        return finalSize;
+    }
+}