feat: add reactor control persistence and tests

src/reactor_sim/logging_utils.py

@@ -0,0 +1,38 @@
+"""Logging helpers for the reactor simulation package."""
+
+from __future__ import annotations
+
+import logging
+from typing import Optional
+
+
+def configure_logging(level: int | str = "INFO", logfile: Optional[str] = None) -> logging.Logger:
+    """Configure a package-scoped logger emitting to stdout and optional file."""
+    resolved_level = logging.getLevelName(level) if isinstance(level, str) else level
+    logger = logging.getLogger("reactor_sim")
+    logger.setLevel(resolved_level)
+    if not logger.handlers:
+        stream_handler = logging.StreamHandler()
+        formatter = logging.Formatter(
+            fmt="%(asctime)s | %(levelname)s | %(name)s | %(message)s", datefmt="%H:%M:%S"
+        )
+        stream_handler.setFormatter(formatter)
+        logger.addHandler(stream_handler)
+        if logfile:
+            file_handler = logging.FileHandler(logfile)
+            file_handler.setFormatter(formatter)
+            logger.addHandler(file_handler)
+    else:
+        for handler in logger.handlers:
+            handler.setLevel(resolved_level)
+        if logfile and not any(isinstance(handler, logging.FileHandler) for handler in logger.handlers):
+            file_handler = logging.FileHandler(logfile)
+            formatter = logging.Formatter(
+                fmt="%(asctime)s | %(levelname)s | %(name)s | %(message)s", datefmt="%H:%M:%S"
+            )
+            file_handler.setFormatter(formatter)
+            logger.addHandler(file_handler)
+    # Keep package loggers self-contained so host apps can opt-in to propagation.
+    logger.propagate = False
+    logging.getLogger().setLevel(resolved_level)
+    return logger