[SW] Introduce Expression Engine API

This is a placeholder JIRA for the new API we need to introduce to support expression engines on Kogito Serverless Workflows.

We currently support JSONPath, but the implementation is pretty straightforward and doesn't have support for "injection" of different languages, like jq.

We need a way to handle multiple expressions support on a workflow definition that would be easy to understand and maintain. And most importantly, be able to extend to other languages in the future.

Blocks KOGITO-5550.