lynkr-dsh-plugin: Registering Lynkr as a Custom OpenAI Provider for DeepSeek Harness

`lynkr-dsh-plugin` is an unofficial plugin that integrates Lynkr, a self-hosted LLM routing gateway, into DeepSeek Harness (dsh). It registers Lynkr as an OpenAI-compatible provider, using its intelligent routing capabilities to automatically select the most cost-efficient model tier across 15+ providers based on request complexity. The plugin supports installation via dsh's plugin manager and automatically configures environment variables to connect to the Lynkr service. Because dsh's plugin API is in a developer preview stage and has not been practically tested, the plugin includes fallback mechanisms: if automatic configuration fails, it outputs a configuration code block for manual addition to ensure service availability.