feat: add BestFitFilter and TileEvaluator for pair filtering and tiling

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

OpenNest.Engine/BestFit/Tiling/TileResult.cs

@@ -0,0 +1,23 @@
+using System.Collections.Generic;
+using OpenNest.Geometry;
+
+namespace OpenNest.Engine.BestFit.Tiling
+{
+    public class TileResult
+    {
+        public BestFitResult BestFit { get; set; }
+        public int PairsNested { get; set; }
+        public int PartsNested { get; set; }
+        public int Rows { get; set; }
+        public int Columns { get; set; }
+        public double Utilization { get; set; }
+        public List<PairPlacement> Placements { get; set; }
+        public bool PairRotated { get; set; }
+    }
+
+    public class PairPlacement
+    {
+        public Vector Position { get; set; }
+        public double PairRotation { get; set; }
+    }
+}