Rework Tagger fork into Curator movie-library manager (PySide6 GUI, pool index, ČSFD import)

src/core/utils.py

@@ -0,0 +1,7 @@
+from pathlib import Path
+
+def list_files(folder_path: str | Path) -> list[Path]:
+    folder = Path(folder_path)
+    if not folder.is_dir():
+        raise NotADirectoryError(f"{folder} není platná složka.")
+    return [file_path for file_path in folder.rglob("*") if file_path.is_file()]