Use ChatGPT (Codex), Claude, and Grok (X Premium) subscriptions as DeepSeek Harness LLM providers — OAuth login in the web UI, no API keys

Permission-first rules, agents, skills and workflows for AI coding agents. One source → native CLAUDE.md, AGENTS.md and GEMINI.md for Claude Code, OpenAI Codex and Google Antigravity. Claude Code plugin + one-line install.