here is the main issue:
Caused by: org.drools.WorkItemHandlerNotFoundException: Could not find work item handler for
which means that you haven't:
- defined name of the task which will be used to execute the work item - most likely your service task - check here
- as you did not define the name most likely you did not register workitem handler for it - check here
- did not provide implementation of the work item handler on consoles classpath - package your handlers as jar and drop them into jbpm-console-server.war/WEB-INF/lib
HTH