While not exactly what you are requesting, the use case you describe of running pre and post test suites seems to fit the functionality of the project Setup Script and Teardown Script (These are both just Groovy Scripts).
I'm not sure how large or complicated your setup and cleanup TestSuites are, or if this is a viable solution for you?
While I have never run complete TestSuites from Groovy, I do call other individual test cases from Groovy, with these "common library" test cases in their own separate TestSuite which is left disabled so they don't get run when the full project is run (hope that makes sense!).
