Improve UI text regarding scope settings on consumers

Problem/Motivation

I am a module maintainer and even I often forget or am confused by the operation/intersection of scopes and roles, particularly as it relates to the scope settings on the consumer configuration. The applicable code is at ScopeRepository::finalizeScopes().

The confusion stems from the fact the scopes configured on the consumer (client) are always issued, and users may additionally request and be issued scopes for roles they hold. I am referencing a few issues I found that stem from this confusion.

The current UI text is:

The roles for this Consumer. OAuth2 scopes are implemented as Drupal roles.
Create a role for every logical group of permissions you want to make available to a consumer.

Which is technically true but not complete.

Steps to reproduce

Proposed resolution

Make this more explicit.

Remaining tasks

User interface changes

API changes

Data model changes