Allow workflow role to transition but not edit content items in a state.

From my previous thread []…

When assigning a Role to a Workflow State, the Assignment field sets what kind of access the Role has to content items in that state. The choices are Assignee (read, edit, and transition), Reader (read only), or None. Is there a way to add additional choices to this? Specifically, I’d like to have an access level that allows a Role to read and transition, but not edit, content items in a given state.

According to the responses in that thread, this feature does not exist in the current product. Several people suggested adding this to the ideas forum, so I have.