dsh-carbon: Carbon Element Data Query Plugin

`dsh-carbon` is a pure Node.js plugin for DeepSeek Harness (DSH), maintained by uckkk, for locally retrieving structured data about the carbon element. It offers two methods: `element_info` for retrieving full details and `element_field` for querying specific fields. To install, run `dsh plugin add github:uckkk/dsh-carbon`; before using it, ensure dependency versions are correct. Since the plugin runs with the current process permissions, it is recommended to review its source code before installation.