There is developer documentation on how to create a new plugin here: https://github.com/openshift/assisted-service/blob/master/docs/dev/olm-operator-plugins.md

What I would like to find out is how to use the existing plugin for the local storage operator (LSO). The local storage operator would be one way to provide a persistent volume to back the cluster 0 assisted-service database.

Currently I cannot find any documentation on how to use OLM operator plugins.