The file_explorer example had two issues:
1. Used heuristic (contains '.') to detect files vs directories, which is unreliable
2. Tried to enter files as directories when clicked, causing errors
Changes:
- Use path.is_file() for accurate file detection
- Use path.is_dir() check before entering a directory
- Rename shadowed 'path' variable to 'path_display'
Fixes#5368
Co-authored-by: BillionClaw <267901332+BillionClaw@users.noreply.github.com>
