Yeah, I would recommend to use AbstractWorkItemHandler as a base class for all your handlers so you'll get access to session.
As it comes to using that handler in console, you could declare your custom work item handlers inside CustomWorkItemHandlers.conf that is located inside gwt-console-server.war/WEB-INF/classess/META-INF. Just one note, I believe session won't be injected into it. If you don't mind to have a handler that is tightly coupled with console code you could look it up using signleton object StatefulKnowledgeSessionUtil.getStatefulKnowledgeSession().
HTH