Normalize non-finite metric export to null

code/scripts/launch_oven_fuller_logging_batch.py

@@ -41,7 +41,7 @@ def _configure_coppeliasim_env() -> None:
 _configure_thread_env()
 _configure_coppeliasim_env()
 
-from rr_label_study.oven_study import _aggregate_summary, _episode_dirs
+from rr_label_study.oven_study import _aggregate_summary, _episode_dirs, _json_safe
 
 
 def _select_episode_indices(
@@ -99,7 +99,7 @@ def _load_metrics(result_dir: Path, episode_names: Sequence[str]) -> List[Dict[s
 def _write_json(path: Path, payload: Dict[str, object]) -> None:
     path.parent.mkdir(parents=True, exist_ok=True)
     with path.open("w", encoding="utf-8") as handle:
-        json.dump(payload, handle, indent=2)
+        json.dump(_json_safe(payload), handle, indent=2, allow_nan=False)
 
 
 def _run_episode(