Assignments unification parser, engine, code gen

At present we have 3 different types of nodes

Throw Nodes (Input)
Catch Nodes (Output)
Activities, UserTasks and WIH, services, lambda (Input/Output)

Error nodes and compensatino nodes requires a different jira for this.

At engine level
https://github.com/kiegroup/kogito-runtimes/blob/main/jbpm/jbpm-flow/src/main/java/org/jbpm/workflow/instance/node/WorkItemNodeInstance.java#L227-L289
or
https://github.com/kiegroup/kogito-runtimes/blob/main/jbpm/jbpm-flow/src/main/java/org/jbpm/workflow/instance/node/WorkItemNodeInstance.java#L312-L384

this code is duplicated all along the jbpm engine e.g.
https://github.com/kiegroup/kogito-runtimes/blob/main/jbpm/jbpm-flow/src/main/java/org/jbpm/workflow/instance/node/SubProcessNodeInstance.java#L93-L154

This jira is to unify that code in one place to prepare the assignment jira.