Review Runtime API

Runtime API is pretty much defined at least in its design, this task is about ensuring it is covering all aspects of the frameworks (configuration, runtime, ui, generic record (aka ObjectMap ...).

Outcome of this task is a checklist document. It can be integrated to the "documentation" module as a "list of feature" documentation page if you think it is more appropriated.

side note on ObjectMap: we can refine this API in another task if needed, we can also take inspiration from jxpath for the "indexation" instead of a flat record access like done currently (~jsonpath/avropath like) -> some discussion is ongoing @tab on that topic