cell_significance: per-cell best-combo gain verdicts (provisional)

cell_significance/cell_best_gain.json

@@ -1,6 +1,6 @@
 {
   "schema_version": "cell-best-gain-v1",
-  "generated_at": "2026-09-10T20:04:29.257655+00:00",
+  "generated_at": "2026-09-10T20:09:34.132047+00:00",
   "methodology_doc": "docs/cell-performance.md",
   "axis": "accuracy",
   "alpha": 0.05,