Shows indexing a new maildir file, silent merging of duplicate message IDs, FileNotEmail for a non-email inside the mail root, and FileError for a path outside it (rejected before it is read). Co-Authored-By: Claude Fable 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_017i7R7ReKJAHGQpitxGXqrb