Add a zsh alias / function to the user's ~/.zshrc, idempotently and safely. Supports both ASCII names (e.g. `gs`, `zxsd`) and 中文 function names (e.g. `中信书店`) — zsh fully supports CJK function identifiers. Trigger when the user says: "加个 alias", "加一个别名", "做个快捷命令", "我想输入 X 就执行 Y", "alias for X", "shortcut for X", "shell alias", or asks to wrap a command behind a single trigger word.
