DeepSeek Harness Plugin: dsh-llm-commandcode

The `dsh-llm-commandcode` plugin integrates the Command Code Provider API into the chat protocol framework of DeepSeek Harness (DSH) via its `PiAiAdapter`. It supports Claude and OpenAI protocols, and provides serialization, SSE, tool calling, and reasoning capabilities, along with account quota tracking (best-effort on the host side) and a Zero Data Retention (ZDR) option. The plugin requires DSH version 0.1.7-alpha.2 or later and must be configured in the UI with model settings and host trust after installation. It supports Headless mode, while keys are securely stored only in the Host credential service.