tools/analyze_samples.py is a COMMITTED symlink into ../tidal-ears, which is
not cloned on the XPS24. rglob could see the path and read_text could not open
it, and _offenders() caught only SyntaxError — so a FileNotFoundError escaped
at import time and the whole module failed COLLECTION.

That is the exact failure this file exists to prevent, turned on itself: the
guard reported nothing rather than reporting a gap, and a guard that cannot run
guards nothing. Skip unreadable paths explicitly.

Verified standalone on the rig interpreter: 3 tests pass, 256 files scanned.