An idea: Set up an interaction for a unit test (using strict, exact matching), but specify that it can be used for stubbing in a later test, and specify the route that it should be matched against (with optional tags?). The Mock Server would write these interactions to a separate file, or add metadata to them in the normal pact file. Then, during an integration test, interactions can be loaded and will act as stubs using "type based" matching (something_like).
This means that our stubs will be verified as well as our mocks.