i'd like having an object representation of a typeset paragraph or even
a page, preferably as a JSON object, but a Lua table is equally good.
My reference is section "4.4 Node lists" of the CLD manual.
Before writing an iterator over the list of nodes of a paragraph,
figuring out all the possible nodes and their fields, i'm wondering if
there's some hidden tool in the ConTeXt coffer to simplify the task.