dsh-grok-auth: DeepSeek Harness Grok Authentication Plugin

dsh-grok-auth is a DeepSeek Harness plugin designed to address the issue that Grok 4.x models cannot be directly accessed via an OAuth subscription. It reuses the official Grok CLI login state (`~/.grok/auth.json`) to bridge the OAuth token to Harness’s `xai` route. The plugin supports browser or device code login, manages token expiration and locking mechanisms, and provides real-time model discovery. It injects subscription quota into request headers, eliminating the need to maintain additional API keys. Note that this plugin is unofficial and may be subject to security limitations and the risk of a lack of official support.