fix(ui): move the saved-nests Find bar above the grid

At the bottom of the form the search box read as part of the Details
panel. It now sits under the Nests header, next to the list it filters,
and comes first in the tab order.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

OpenNest/Forms/SavedNestsForm.cs

@@ -307,18 +307,23 @@ public sealed class SavedNestsForm : Form
         findBar.Controls.Add(nextButton);
         findBar.Controls.Add(summaryLabel);
 
-        var bottom = new TableLayoutPanel
+        // The find bar sits between the Nests header and the grid it filters, and comes
+        // first in the tab order.
+        var findPanel = new TableLayoutPanel
         {
-            Dock = DockStyle.Bottom,
+            Dock = DockStyle.Top,
             AutoSize = true,
             ColumnCount = 1,
-            Padding = new Padding(3, 3, 3, 6),
+            Padding = new Padding(3, 0, 3, 3),
+            TabIndex = 0,
         };
-        bottom.ColumnStyles.Add(new ColumnStyle(SizeType.Percent, 100));
-        bottom.Controls.Add(findBar);
+        findPanel.ColumnStyles.Add(new ColumnStyle(SizeType.Percent, 100));
+        findPanel.Controls.Add(findBar);
+        nestGrid.TabIndex = 1;
+        split.Panel1.Controls.Add(findPanel);
+        split.Panel1.Controls.SetChildIndex(findPanel, 1);
 
         Controls.Add(split);
-        Controls.Add(bottom);
 
         Load += (_, _) =>
         {