Hi Mauricio,
I have been looking into to the jbpm-gwt-core and I did not find anything.
The fact is that in the jbpm-gwt-console-server project, there is in the target folder tree structure with some java classes that are the ones that define the REST interface. They are in,
jbpm-gwt-console-server/target/jbpm-gwt-console-server-5.2.0-Snapshot/WEB-INF/classes/org/jboss/bpm/console/server
Now the problem is that because they are in the target they are getting rebuilt.
I have looked everywhere in the jbpm-gwt project and I have not been able to identify where these files are coming from.