Function truncate_path_tail 

fn truncate_path_tail(path: &str, max_width: usize) -> String

Truncate a filesystem path to show only the most specific directories. Walks forward to the first path separator after the truncation point to avoid splitting mid-component.

Examples:

• C:\Users\user\AppData\...\SaveGames → …\AppData\...\SaveGames
• A short path that fits max_width is returned unchanged.