Mark SkeletonModificationStack3D and related as deprecated.
Mark local bone override and axis functions deprecated in Skeleton3D api.
Fix array property glitch in SkeletonModificationStack2D
Mark SkeletonModificationStack2D and related APIs as experimental. Mark SkeletonIK3D as deprecated.
This makes it easier to spot syntax errors when editing the
class reference. The schema is referenced locally so validation
can still work offline.
Each class XML's schema conformance is also checked on GitHub Actions.
For the time being we don't support writing a description for those, preferring
having all details in the method's description.
Using self-closing tags saves half the lines, and prevents contributors from
thinking that they should write the argument or return documentation there.