jamubc/opencode-ponytail-v2 ? reverse-engineered prompt

Build me an OpenCode 2.x plugin called Ponytail that makes my coding agent write the minimum amount of code that still does the job.

I want it to work like the upstream Ponytail plugin, but ported so OpenCode 2.x will actually load it. It should inject the current Ponytail rules into every request, add the Ponytail commands and skills, and let me switch between lite, full, ultra, and off from inside the chat. If I change the level, save it so the setting stays shared across sessions and other Ponytail compatible tools.

Please keep it focused on OpenCode 2.x only, no old version fallback, and make sure it behaves as closely as possible to the original upstream plugin. If you need to look up current OpenCode docs or confirm API details online, go ahead.