The goal is to provide an interface to the user, to allow to define variables that are contextual to a node (not global variables defined earlier in the process).
The tab should list, for information, existing built-in variables, before offering the schema-like edit interface. Existing variables are:
- nodeId
- nodeStartTime
- assignees
- comment
- status
(To be completed)
Like for global workflow variables, the schema name and prefix is not editable (maybe user doesn't have to know it is a schema implementation behind the scene)