HunYiSage/dsh-purge ? reverse-engineered prompt

Build me a local plugin for DeepSeek Harness that adds a small dock next to the session title, with a Clean page and a Drill page. On Clean, I want to see the current patch status, edit the default prompt, choose between multiple rule sets, and be able to apply, restore, or uninstall the changes easily. It should automatically check the install on start and reapply anything that got overwritten, since npm updates can wipe local changes.

Please make it work with the official desktop app and web app, and have it look for the DSH install in the usual local places instead of hardcoding paths. Keep it focused on my own machine and local lab use only. If you need to, look up the current docs online so it matches the right Harness version. Also make sure the code is organized so I can swap prompts by model and keep the default prompt editable in the UI.