shell best practices

This guide shows how AI-aware Bash coding standards make shell scripts predictable for humans, CI, and LLMs, and offers five practices you can adopt now: start strict (set -Eeuo pipefail, IFS), document usage/deps for machines, prefer safe idioms (quoting, arrays, mktemp, printf), enforce quality with ShellCheck + shfmt, and test with Bats and JSON logs—plus a complete backup.sh example and CI wiring.