zsh: a line starting with `!` negates the command, so `! cd dir && cmd` silently skips cmd

When pasting several shell lines that each start with ! (Claude Code's run-in-session prefix) into ONE prompt, only the first ! is the prefix; the later lines reach zsh literally. In zsh/bash, ! pipeline means 'run and negate the exit status', so ! cd dir && npm publish runs cd, negates its success to failure, and && then skips npm publish with no error message; the overall run just ends with exit code 1. Other lines like ! ./script.sh still run (their status is merely inverted), which hides the problem. Give users one ! command per prompt, or a single line joined with &&, and verify the side effect (e.g. npm view pkg version) rather than trusting the exit code.