[Request]: `container system property ls` includes plugin settings values.

### Feature or enhancement request details

`container system property ls` should output the setting values for plugins as well as for core configuration.

### Code of Conduct

- [x] I agree to follow this project's Code of Conduct

Start by locating the implementation of the `container system property ls` command and how it gathers core configuration values. Run the command with plugin settings present to observe the current output. Done means plugin setting values appear alongside core configuration values, with tests updated or added if the command has coverage.

Written by the indexing model from the issue text.