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.
Fix issue when two skeletons end up directly parented.
Prevent animating TRS for skinned Mesh node.
Fix animating weights on meshes with targets but no weights.
Aaron Franke
Hugo Locurcio
Michael Alexsander Silva Dias
Marcel Admiraal
Lyuma
Rémi Verschelde