Kernel rig: 545 graded on its volume (the frame less its 0.5 mm-offset cavity, sharp to rounded concave edges), its sealed pillar void and box

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

tests/kernel-cases/shell/545-shell-ring-cut-frame-open-at-an-outer-wall/expected.json

@@ -10,5 +10,17 @@
  "volume_mm3": 21044.0,
  "tolerance": {
   "rel": 1e-06
+ },
+ "bbox": {
+  "min": [
+   0,
+   0,
+   0
+  ],
+  "max": [
+   100,
+   100,
+   30
+  ]
  }
 }