[Question] Autogenerated description for IAM Roles created by CDK

## :question: General Issue

Now that #6179 has landed, it would be really nice if we can have autogenerated descriptions for roles created automatically by CDK. This would be really helpful, especially if you're pushing CDK within your team and there are 100's of roles, and they don't necessarily like add IAM Role description field (see screenshot below).


### The Question

Where would this logic go? In `aws-iam` package, or in each package should populate `description` field separately. In any case tons of tests would have to be fixed all across the board.

I would just like to start a discussion and see where it goes.

Start by reading the context from #6179 and comparing the aws-iam package with the alternative of populating descriptions in each package. The issue does not name specific files, tests, or acceptance criteria; a maintainer decision is needed before implementation can be scoped.

Written by the indexing model from the issue text.