Robustness goldens: record seeds 31 and 83 after #1581 and #1495 (#1657)

Seed 31: #1581 refuses a fillet selection with an earlier round's smooth seam instead of re-rounding another nearby edge. Seed 83: #1316 was recorded before its branch took in #1495, whose shell keeps the wall beside a concave edge.

Co-Authored-By: Claude Opus 5.5 <[email protected]>

tests/robustness/goldens.json

@@ -32,7 +32,7 @@
   "28": {"area":2394.691384,"bodies":1,"edges":15,"error":null,"faces":9,"outcome":"ok","rejected":0,"shells":2,"steps":["revolved section","join cylinder"],"unsupported":0,"volume":5902.121375},
   "29": {"area":6965.599057,"bodies":1,"edges":74,"error":null,"faces":30,"outcome":"ok","rejected":0,"shells":1,"steps":["extruded profile","shell","join cylinder"],"unsupported":0,"volume":3977.885339},
   "30": {"area":853.525389,"bodies":1,"edges":23,"error":null,"faces":10,"outcome":"ok","rejected":0,"shells":1,"steps":["revolved section","chamfer"],"unsupported":0,"volume":1337.14821},
-  "31": {"area":10198.42294,"bodies":3,"edges":67,"error":null,"faces":29,"outcome":"ok","rejected":1,"shells":3,"steps":["box","cut box","fillet","join box","fillet","circular pattern","cut box","circular pattern"],"unsupported":0,"volume":56408.3612},
+  "31": {"area":10221.945046,"bodies":3,"edges":68,"error":null,"faces":29,"outcome":"ok","rejected":2,"shells":3,"steps":["box","cut box","fillet","join box","circular pattern","cut box","circular pattern","hole"],"unsupported":0,"volume":56397.581359},
   "32": {"area":3220.802769,"bodies":1,"edges":51,"error":null,"faces":19,"outcome":"ok","rejected":0,"shells":1,"steps":["revolved section","cut sphere","cut box","cut box","join box"],"unsupported":0,"volume":7565.955897},
   "33": {"area":5286.736353,"bodies":2,"edges":59,"error":null,"faces":27,"outcome":"ok","rejected":0,"shells":3,"steps":["revolved section","fillet","join box","cut cylinder","chamfer","join box","chamfer","fillet"],"unsupported":2,"volume":13858.467983},
   "34": {"area":1086.305562,"bodies":1,"edges":30,"error":null,"faces":14,"outcome":"ok","rejected":0,"shells":1,"steps":["revolved section","cut sphere","hole"],"unsupported":0,"volume":2134.365275},
@@ -84,7 +84,7 @@
   "80": {"area":8652.533342,"bodies":1,"edges":20,"error":null,"faces":9,"outcome":"ok","rejected":0,"shells":1,"steps":["box","fillet","fillet"],"unsupported":0,"volume":37387.449469},
   "81": {"area":4001.847983,"bodies":2,"edges":75,"error":null,"faces":29,"outcome":"ok","rejected":1,"shells":2,"steps":["revolved section","cut sphere","circular pattern","rectangular pattern","hole","join cylinder","join box","cut sphere"],"unsupported":2,"volume":13139.658749},
   "82": {"area":3195.487112,"bodies":1,"edges":30,"error":null,"faces":13,"outcome":"ok","rejected":0,"shells":1,"steps":["box","hole","circular pattern","cut box"],"unsupported":0,"volume":5902.162954},
-  "83": {"area":8489.059183,"bodies":1,"edges":97,"error":null,"faces":35,"outcome":"ok","rejected":0,"shells":2,"steps":["box","join box","rectangular pattern","shell","fillet","cut sphere","join box"],"unsupported":1,"volume":6217.394627},
+  "83": {"area":8632.834978,"bodies":1,"edges":95,"error":null,"faces":35,"outcome":"ok","rejected":0,"shells":2,"steps":["box","join box","rectangular pattern","shell","cut sphere","join box","fillet"],"unsupported":2,"volume":6339.218896},
   "84": {"area":4906.192237,"bodies":1,"edges":67,"error":null,"faces":25,"outcome":"ok","rejected":2,"shells":1,"steps":["extruded profile","fillet","hole","hole","cut cylinder","cut box","fillet"],"unsupported":0,"volume":14219.865875},
   "85": {"area":3309.210936,"bodies":1,"edges":57,"error":null,"faces":24,"outcome":"ok","rejected":1,"shells":2,"steps":["revolved section","fillet","cut sphere","circular pattern","join cylinder","hole","join box"],"unsupported":0,"volume":6904.455565},
   "86": {"area":7885.256491,"bodies":1,"edges":66,"error":"offset: a corner whose faces don't meet the same way after t","faces":28,"outcome":"failed","rejected":0,"shells":3,"steps":["extruded profile","join cylinder","join cylinder","circular pattern","rectangular pattern","shell"],"unsupported":2,"volume":21498.10695},
@@ -125,6 +125,7 @@
   {"reason":"Seed 83 builds: a shell splits a saddle corner (convex and concave edges in turn) into two corners","seeds":[83]},
   {"reason":"seed 15 now cuts around a sealed void","seeds":[15]},
   {"reason":"#1490: when the last-resort nudge fails both ways, two more screw axes are tried; seed 63's final box join (its face 0.00005 mm off the half-ring's cut face) now builds instead of being refused with an implausible volume, and the design goes on to its fillet","seeds":[63]},
-  {"reason":"a prism cut in a column round the tool (prism_local): seed 65's rectangular pattern (step 4, a second half-cylinder groove overlapping the first, in a block with a rounded vertical edge) is now built by the exact 2D route in a column clear of the round, where the B-rep tries left it with split edges. The step's part has the 10 faces, 24 edges and 16 vertices it should (28 edges and 18 vertices before), and its volume is 45145.383 mm³ against 45145.214 (exactly 45145.103, both within the mesh measure); the generator then picks other edges for its step 7 fillet, so the run ends on another design (45143.48 mm³, 15 faces)","seeds":[65]}
+  {"reason":"a prism cut in a column round the tool (prism_local): seed 65's rectangular pattern (step 4, a second half-cylinder groove overlapping the first, in a block with a rounded vertical edge) is now built by the exact 2D route in a column clear of the round, where the B-rep tries left it with split edges. The step's part has the 10 faces, 24 edges and 16 vertices it should (28 edges and 18 vertices before), and its volume is 45145.383 mm³ against 45145.214 (exactly 45145.103, both within the mesh measure); the generator then picks other edges for its step 7 fillet, so the run ends on another design (45143.48 mm³, 15 faces)","seeds":[65]},
+  {"reason":"Seed 31: #1581 no longer maps a pick on an earlier round's seam to some other nearby edge; the second fillet's selection includes the smooth seam at [2, 27.5, 13.5] beside the first round, which is now refused (no corner to round) instead of silently re-rounding a different edge at 1 mm, so the run goes on to a hole. Seed 83: #1316 was recorded before its branch took in #1495; with #1495's shell (an open face next to a concave edge no longer cuts the wall past it) the shelled part keeps more wall (6217 to 6339 mm3), its edges differ, and the 2.5 mm fillet of the first run is not picked; a later fillet is refused as not supported yet (an end face parallel to the edge)","seeds":[31,83]}
  ]
 }