Automatically set-up user's workflow RBAC for them

# Summary

Despite adding a lot of docs, many new users struggle with RBAC. RBAC is hard. Why don't we just have the controller set it up automatically?

# Use Cases

To make it much easier to use.

Relates to #6886

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**Message from the maintainers**:

Impacted by this bug? Give it a 👍. We prioritise the issues with the most 👍.

The issue names the workflow controller and RBAC but does not identify files, tests, or specific entry points. Start by reviewing related issue #6886 and the existing RBAC documentation to clarify the requested behavior. Done requires an agreed automatic setup approach that addresses the stated new-user use case.

Written by the indexing model from the issue text.