oracle: quantities of a generated mesh can be gated by their tolerance alone ("fixture": false)

The bracket's tet mesh is not bit-identical across platforms (#115): its fillet peak is 213.31 MPa
on macOS and 212.42 on Linux CI, which turned the oracle job red after #110. Those two quantities
are no longer frozen; the page names them mesh-dependent instead of printing one platform's value.

Co-Authored-By: Claude Opus 5.5 <[email protected]>
Claude-Session: https://claude.ai/code/session_01NmAttHhUZTokgPeEJia8sm

tests/oracle/filleted-bracket-fillet-stress-coarse/expected.json

@@ -19,7 +19,9 @@
    "tolerance": {
     "relative": 0.03
    },
-   "reason": "the four-level study gives 213.3, 210.6, 214.3, 213.3 MPa (2k to 13.5k elements): the bending stress is converged across the fillet, and the peak nodal value moves only with which of the fillet's tessellation lines (fixed angles, through every level) carries the largest node, by under 2%"
+   "reason": "the four-level study gives 213.3, 210.6, 214.3, 213.3 MPa (2k to 13.5k elements): the bending stress is converged across the fillet, and the peak nodal value moves only with which of the fillet's tessellation lines (fixed angles, through every level) carries the largest node, by under 2%",
+   "fixture": false,
+   "fixture_reason": "the peak depends on the tet mesh generated from SolidCraft's tessellation, which is not bit-identical across platforms (212.4 MPa on Linux CI against 213.3 on macOS for the same recipe; issue #115): the 3% reference tolerance gates it until meshing is reproducible across platforms"
   },
   {
    "id": "reaction",

tests/oracle/filleted-bracket-fillet-stress-coarse/fixture.json

@@ -1,12 +1,8 @@
 {
   "note": "FieldCraft's accepted results for this case, written by `cargo xtask oracle --bless`. A result outside its band fails CI.",
   "values": {
-    "fillet_peak": {
-      "band": 2.1330697455903942e-7,
-      "value": 213.30697455903942
-    },
     "reaction": {
-      "band": 2.000000000000858e-6,
+      "band": 2.000000000000858e-06,
       "value": -2000.0000000008579
     }
   }

tests/oracle/filleted-bracket-fillet-stress/expected.json

@@ -19,7 +19,9 @@
    "tolerance": {
     "relative": 0.03
    },
-   "reason": "the four-level study gives 213.3, 210.6, 214.3, 213.3 MPa (2k to 13.5k elements): the bending stress is converged across the fillet, and the peak nodal value moves only with which of the fillet's tessellation lines (fixed angles, through every level) carries the largest node, by under 2%"
+   "reason": "the four-level study gives 213.3, 210.6, 214.3, 213.3 MPa (2k to 13.5k elements): the bending stress is converged across the fillet, and the peak nodal value moves only with which of the fillet's tessellation lines (fixed angles, through every level) carries the largest node, by under 2%",
+   "fixture": false,
+   "fixture_reason": "the peak depends on the tet mesh generated from SolidCraft's tessellation, which is not bit-identical across platforms (212.4 MPa on Linux CI against 213.3 on macOS for the same recipe; issue #115): the 3% reference tolerance gates it until meshing is reproducible across platforms"
   },
   {
    "id": "reaction",

tests/oracle/filleted-bracket-fillet-stress/fixture.json

@@ -1,12 +1,8 @@
 {
   "note": "FieldCraft's accepted results for this case, written by `cargo xtask oracle --bless`. A result outside its band fails CI.",
   "values": {
-    "fillet_peak": {
-      "band": 2.1330693756948646e-7,
-      "value": 213.30693756948645
-    },
     "reaction": {
-      "band": 2.0000000000001007e-6,
+      "band": 2.0000000000001007e-06,
       "value": -2000.0000000001007
     }
   }