updates :)

logger.py

@@ -9,7 +9,7 @@ Usage anywhere in the codebase:
 
 Environment variables:
     LOG_LEVEL   — DEBUG | INFO | WARNING | ERROR | CRITICAL  (default: INFO)
-    LOG_FILE    — path to write a rotating log file (optional)
+    LOG_FILE    — path to write a rotating log file           (default: logs/seed.log)
 """
 from __future__ import annotations
 
@@ -28,7 +28,7 @@ _LEVEL_MAP: Final = {
 }
 
 _LOG_LEVEL: int = _LEVEL_MAP.get(os.getenv("LOG_LEVEL", "INFO").upper(), logging.INFO)
-_LOG_FILE: str | None = os.getenv("LOG_FILE")
+_LOG_FILE: str = os.getenv("LOG_FILE", "logs/seed.log")
 
 # ── ANSI colour codes (console only) ─────────────────────────────────────────
 _RESET  = "\033[0m"
@@ -86,14 +86,14 @@ def _build_root_logger() -> logging.Logger:
     console.setFormatter(_ColourFormatter())
     root.addHandler(console)
 
-    # Optional rotating file handler
-    if _LOG_FILE:
-        fh = logging.handlers.RotatingFileHandler(
-            _LOG_FILE, maxBytes=10 * 1024 * 1024, backupCount=5, encoding="utf-8"
-        )
-        fh.setLevel(_LOG_LEVEL)
-        fh.setFormatter(_FILE_FMT)
-        root.addHandler(fh)
+    # Rotating file handler (always on)
+    os.makedirs(os.path.dirname(_LOG_FILE), exist_ok=True)
+    fh = logging.handlers.RotatingFileHandler(
+        _LOG_FILE, maxBytes=10 * 1024 * 1024, backupCount=5, encoding="utf-8"
+    )
+    fh.setLevel(_LOG_LEVEL)
+    fh.setFormatter(_FILE_FMT)
+    root.addHandler(fh)
 
     root.propagate = False
     return root