Relative script paths resolved against HERMES_HOME/scripts/ were not
validated to stay within that directory. Paths like '../../etc/passwd'
could escape and be executed as Python.
Fix: resolve the path and verify it stays within scripts_dir using
Path.relative_to(). Also apply redact_sensitive_text() to script stdout
before LLM injection — same pattern as execute_code sandbox output.
Cherry-picked from PR #5093 by memosr (fixes 1 and 3; absolute path
restriction dropped as too restrictive for the feature's design intent).