Lay out the design that everything else builds on: a small frozen kernel plugins treat as a shared language, the plugin contract, the two-assembly hot-reload model, and the build order through M4. Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01N1qPfzq8TDCUMFMV3UwV5N