Fixed urgent

- Job profile didn't wait for everything to load before doing stuff. It worked before because the supermodel was faster. It's now used for the user as well.
- Some db endpoints don't handle user slugs yet. This is an urgent fix for one of those cases (user avatar). Introduced `findBySlugOrId` to mimix the original `findById`. I like most code to be id-or-slug agnostic as possible to keep stuff from breaking down.