[DPE-4583] - docs: add CC tutorial

[marcoppenheimer]

Changes Made

docs: add CC tutorial

• Tutorial covers the action implementation with expected output, for full, add and remove modes
• Vale is complaining about execute and various keywords, probably need to add them to the style guide in https://github.com/canonical/praecepta

[marcoppenheimer]

Closing as will be merged in https://github.com/canonical/kafka-k8s-operator/pull/128