@xia-sc/dsh-language-policy: Pin the Simplified Chinese language policy to the end of the system prompt

DSH host-only bundle appends simplified Chinese reasoning/response strategies to the end of the system prompt within a system role, addressing the issue where AGENTS.md, used as guidance injection, fails to suppress English drift in long conversations. The article introduces the working principle, installation commands, `enabled/text` configuration, two-level verification of static analysis and prompt implementation, A/B testing results, compatibility, and boundaries (does not guarantee 100% Chinese support, with minimal preset exceptions). The plugin features zero dependencies, pure appending, and does not overwrite upstream configurations. It is maintained by xia-sc under the MIT license.