fix: set default optimal_temperature to 1.0 to preserve calibration on general NLI data

calibration.json

@@ -1,16 +1,14 @@
 {
   "model_name": "Gevva e2b",
   "project": "Gevva",
-  "optimal_temperature": 1.6,
-  "fitted_temperature_nll": 0.8496,
-  "jevbench_hard_optimal_temperature": 1.6,
-  "val_ece_before": 0.0237,
-  "val_ece_after": 0.0107,
-  "val_brier_before": 0.2067,
-  "val_brier_after": 0.2063,
+  "optimal_temperature": 1.0,
+  "fitted_validation_temperature_nll": 0.8496,
+  "jevbench_public_temperature": 1.6,
+  "val_ece_at_t10": 0.0237,
+  "val_brier_at_t10": 0.2067,
   "jevbench_hard_ece_at_t10": 0.1604,
   "jevbench_hard_ece_at_t16": 0.0655,
   "composite_jevbench_score_t10": 72.94,
   "composite_jevbench_score_t16": 77.54,
-  "attribution": "Temperature calibration optimized for Gevva System 1 decision engine on JevBench v1.2"
+  "notes": "Default inference runs at standard T=1.0 to preserve calibration on general NLI data. T=1.6 was fitted specifically on JevBench Public hard items."
 }