Update dmptool-types to support "description" for outputTypes

Currently, only `label` and `value` are saved for custom output types. We need to add `description` to the schema so that we have it for the `info icons`:

<img width="838" height="807" alt="Image" src="https://github.com/user-attachments/assets/008ca670-6719-48c4-ac56-01a8e163272d" />