Let GLTF labeled assets be accessed by their names

[viridia]

What problem does this solve or what need does it fill?

Most of my GLTF assets contain multiple scenes - they are catalogs of objects. It's cumbersome to have to look up scenes in "named_scenes", it would be nice if I could simply load the named scene (using the name I assign in Blender) as a labeled asset. I realize there's an issue because names can collide, but I think there's a simple solution.

What solution would you like?

The solution is to use prefixes. A material named "Foo" will have a label "Material.Foo".

For scenes, we could either use "Scene.", or alternatively since loading scenes is so common, make scenes the exception that don't require a label. So the "SmallWoodenTable" object in "carpentry.glb" would either be "carpentry.glb#Scene.SmallWoodenTable" or "carpentry.glb#SmallWoodenTable".

Of course, there's still a possibility of collisions, but people will quickly learn not to author assets that have name collisions.

What alternative(s) have you considered?

Currently I'm dereferencing the asset and then looking up in named_scenes, but this requires a whole extra system to peek inside the asset once it's loaded. Not ideal.

Using numbered scenes, e.g. "Scene0" is a total non-starter because the numbers aren't stable.

[mockersf]

duplicate of #10715