feat: handle SubProgramCall offsets in BoundingBox and Rotate

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

OpenNest.Core/CNC/Program.cs

@@ -89,6 +89,17 @@ namespace OpenNest.CNC
                 {
                     var subpgm = (SubProgramCall)code;
 
+                    if (subpgm.Offset.X != 0 || subpgm.Offset.Y != 0)
+                    {
+                        var cos = System.Math.Cos(angle);
+                        var sin = System.Math.Sin(angle);
+                        var dx = subpgm.Offset.X - origin.X;
+                        var dy = subpgm.Offset.Y - origin.Y;
+                        subpgm.Offset = new Geometry.Vector(
+                            origin.X + dx * cos - dy * sin,
+                            origin.Y + dx * sin + dy * cos);
+                    }
+
                     if (subpgm.Program != null)
                         subpgm.Program.Rotate(angle, origin);
                 }
@@ -422,7 +433,10 @@ namespace OpenNest.CNC
                     case CodeType.SubProgramCall:
                         {
                             var subpgm = (SubProgramCall)code;
-                            var box = subpgm.Program.BoundingBox(ref pos);
+                            var subPos = subpgm.Offset.X != 0 || subpgm.Offset.Y != 0
+                                ? new Vector(subpgm.Offset.X, subpgm.Offset.Y)
+                                : pos;
+                            var box = subpgm.Program.BoundingBox(ref subPos);
 
                             if (box.Left < minX)
                                 minX = box.Left;

OpenNest.Tests/CuttingStrategy/HoleSubProgramTests.cs

@@ -158,4 +158,40 @@ public class HoleSubProgramTests
         // But different offsets
         Assert.NotEqual(calls[0].Offset.X, calls[1].Offset.X);
     }
+
+    [Fact]
+    public void Program_BoundingBox_IncludesSubProgramOffset()
+    {
+        var sub = new Program(Mode.Incremental);
+        sub.Codes.Add(new LinearMove(1, 0));
+
+        var main = new Program(Mode.Absolute);
+        main.SubPrograms[1] = sub;
+        main.Codes.Add(new SubProgramCall { Id = 1, Program = sub, Offset = new Vector(10, 20) });
+
+        var box = main.BoundingBox();
+
+        // Sub-program line goes from (10,20) to (11,20)
+        Assert.True(box.Right >= 11);
+        Assert.True(box.Top >= 20);
+    }
+
+    [Fact]
+    public void Program_Rotate_RotatesSubProgramCallOffsets()
+    {
+        var sub = new Program(Mode.Incremental);
+        sub.Codes.Add(new LinearMove(1, 0));
+
+        var main = new Program(Mode.Absolute);
+        main.SubPrograms[1] = sub;
+        main.Codes.Add(new SubProgramCall { Id = 1, Program = sub, Offset = new Vector(10, 0) });
+
+        // Rotate 90 degrees CCW around origin
+        main.Rotate(System.Math.PI / 2);
+
+        var call = main.Codes.OfType<SubProgramCall>().First();
+        // (10, 0) rotated 90 CCW = (0, 10)
+        Assert.Equal(0, call.Offset.X, 1);
+        Assert.Equal(10, call.Offset.Y, 1);
+    }
 }