* Output a single `.sh` script using `cat` so it can be restored directly.
* No placeholders, only real, production-ready code.
* No comments, no explanations, no extra text.
* Follow KISS principles.
* Provide a complete, professional, working solution.
* If the script is too long, split into multiple parts, but always return the **entire code**.
* Output must be **only the code**, nothing else.