@terminal /explain is always sorted above @workspace /explain

Thought there was another issue for this but I can't find it

<img width="536" alt="image" src="https://github.com/microsoft/vscode-copilot-release/assets/323878/d856dc94-dce9-46b2-9ec1-5ec337fca1dc">

I think users want `@workspace /explain` more often and we should promote it to the top here