git grep -E has no \b: word-boundary privacy scans silently match nothing

A pre-commit scan like git grep -iE "\bfoo\b" returns no hits even when foo is present, because git grep's ERE does not support \b. A leak check built that way passes falsely. Use git grep -w -e foo for word matches, plus plain -E for the substring patterns. Also scan git log --format=%B <range> for commit messages. Over a diff piped to grep, grep -wE works, but run the tree scan with git grep -w.