perf: remove no-op AutoNester.Optimize calls from fill pipelines

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

OpenNest.Engine/StripNestEngine.cs

@@ -1,5 +1,4 @@
 using OpenNest.Engine.Fill;
-using OpenNest.Engine.Nfp;
 using OpenNest.Geometry;
 using System;
 using System.Collections.Generic;
@@ -123,9 +122,6 @@ namespace OpenNest
                 }
             }
 
-            // NFP optimization pass — re-place parts using geometry-aware BLF.
-            allParts = AutoNester.Optimize(allParts, Plate);
-
             // Deduct placed quantities from original items.
             foreach (var item in items)
             {