[wip] reintroduce Warnings on customclass usage

[RonnyPfannschmidt]

while resolving i found that we do have quite a mess in there because we register a node as a plugin, which in turn gets parsed for factories

i opted into ignoring plain nodes for factory parsing for now,
but that solution is incomplete

however it seems strictly impossible to implement this bit cleanly without breaking the world,
as introducing a session interaction plugin implementing the needed api

[nicoddemus]

Changed the target branch to features. 😉

Not sure what this entails right now, I will have to take a look at the collection code more carefully to understand what's going on.

CI failed as expected because we turned warnings into errors to avoid breaking test suites that do the same. 😁

[nicoddemus]

@RonnyPfannschmidt gentle ping. 👍

[RonnyPfannschmidt]

@nicoddemus this one is on hiatus, i will resolveit hopefully soon

[RonnyPfannschmidt]

closing this one as the rebase failed and made more mess than worth it