[wip] make everything except extensions autoloadable

[solnic]

@gmcgibbon @rafaelfranca 👋🏻 FYI this is a follow-up after your original autoload work but it uses zeitwerk. I need to tweak zeitwerk loader so that it knows how to deal with extension files (or just move files around a bit) to finish this PR. Overall, this looks very promising. Notice that it uses dry-core/configurable/types from main here because those are now autoloadable via zeitwerk as well. Once this one's working too, I'll make dry-validation autoloadable and then we could test it all out 😅 Assuming everything works fine, I'll release all of the things and we should end up with a major boot time speed up ⚡

[rafaelfranca]

🎉

[solnic]

I closed this this since it was done in other PRs eventually