dsh-plugin-8r: DSH's 8R local determination plugin

dsh-plugin-8r is a local judgment plugin for DeepSeek Harness (DSH), maintained by SensenMeng. Its core function is to automatically inject a bold "诶！…" prefix at the beginning of the AI response when a user message triggers a specific rule (8R) via local JavaScript logic. This process is completed entirely locally; the model does not need to understand the rules and does not consume context or tokens, thereby avoiding reliance on model judgment. The plugin uses `agent/pre-step` for judgment, injects the prefix into the stream output, supports failure retry, and prevents duplicate injection within the same turn. It only takes effect for the main session, excluding sub-agent messages, and provides a local diagnostic interface. Installation requires executing an add command in the DSH profile directory and restarting, and depends on the dependency `@de...