Function has_long_sequential_run 

fn has_long_sequential_run(s: &str) -> bool

Checks if a string contains a long consecutive sequential run.

This detects patterns like “12345678” or “abcdefgh” by looking for consecutive runs of characters where each differs from the previous by +1 or -1. Random-looking IDs (like UUIDs) may have scattered sequential pairs but not long runs.