fix(aggregate): Handle string path in _build_files_section_from_items

src/aggregate.py

@@ -194,7 +194,8 @@ def _build_files_section_from_items(file_items: list[dict[str, Any]]) -> str:
   if path is None:
    sections.append(f"### `{entry}`\n\n```text\n{content}\n```")
   else:
-   suffix = path.suffix.lstrip(".") if path.suffix else "text"
+   path_obj = Path(path) if isinstance(path, str) else path
+   suffix = path_obj.suffix.lstrip(".") if path_obj.suffix else "text"
    original = entry if "*" not in entry else str(path)
    sections.append(f"### `{original}`\n\n```{suffix}\n{content}\n```")
  return "\n\n---\n\n".join(sections)