Loading does not load port values

[liamhuber]

As noted by Joerg. E.g. in the canonical example notebook if you change the species from "Fe" to "Al", save, and reload the session, you'll see it reverts to "Fe".

AFAIK ryven itself handles saving and loading this data fine, so I probably broke the behaviour when I patched ryvencore to use the defaults provided in the node definition.

I'm currently locked out of a bunch of github behaviours, but this is label:bug assignees:liamhuber.