Add provenance sidecar for BlockGCN_seed42

checkpoints/external/best_BlockGCN_seed42.provenance.json

@@ -0,0 +1,29 @@
+{
+  "model_name": "BlockGCN",
+  "model_class": "BlockGCNModel",
+  "feature_method": "raw_33_xyz",
+  "seed": 42,
+  "git_sha": "unknown",
+  "git_dirty": true,
+  "saved_timestamp": "2026-10-03 07:31:46 UTC",
+  "epoch": 121,
+  "total_epochs": 140,
+  "best_metric_value": 0.7320637732506643,
+  "val_loss": 1.4373335799827605,
+  "val_acc": 0.7320637732506643,
+  "val_macro_f1": 0.7220216257355234,
+  "hyperparameters": {
+    "optimizer": "SGD",
+    "base_lr": 0.05,
+    "momentum": 0.9,
+    "nesterov": true,
+    "weight_decay": 0.0004,
+    "warm_up_epoch": 5,
+    "steps": [
+      110,
+      120
+    ]
+  },
+  "checkpoint_file": "best_BlockGCN_seed42.pt",
+  "checkpoint_sha256": "cb4b21ce67338089d22f3d22f16f89e6cf7eaa1724d4a1aed36f2a25fe5b034f"
+}