P2: Important Description
https://doc-snapshots.qt.io/qt6-dev/qml-qtquick3d-assetutils-runtimeloader.html
https://www.qt.io/blog/what-is-new-in-qt-quick-3d-6.0
the runtimeloader support loading gltf directly, and quick3d suppor animation in gltf.
we need detailed doc and examples for how to use it.
what about the state of gltf 2.0 supporting in quick3d?
which feature is supported, which is not supported, if supported, how to use it, examples is expected.