shellcraft
Writes portable POSIX sh scripts with getoptions argument parsing, single-file builds, and production patterns (traps, temp files, logging, pipelines). Triggers: shell script, sh script, bash script, CLI tool, command-line tool, getoptions, argument parsing, Makefile recipe, cron job, init script, git hook, CI/CD shell step, deployment script, automation task. Do NOT activate for Python, Node.js, or other non-shell scripting tasks.
