Fix asset container instantiation with parented instanced nodes

[carolhmj]

Fix #13454

I don't think there's any way around using some kind of dependency graph to instantiate nodes in the correct order but if anyone has a simpler idea I'd love to hear it :D

[bjsplat]

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[Popov72]

Only a few comments, great work!

[bjsplat]

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[Popov72]

Shouldn't we use the same default naming than before when cloning / instantiating new nodes? i.e., adding "Clone of " or "instance of" as instantiateHierarchy is doing, to avoid a breaking change?

[bjsplat]

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[bjsplat]

Please make sure to label your PR with "bug", "new feature" or "breaking change" label(s).
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[bjsplat]

Please make sure to label your PR with "bug", "new feature" or "breaking change" label(s).
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[bjsplat]

Please make sure to label your PR with "bug", "new feature" or "breaking change" label(s).
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[bjsplat]

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[bjsplat]

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[bjsplat]

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[RaananW]

Great! Just a few comments

[aWeirdo]

I think this broke something when using AssetContainer.instantiateModelsToScene()
Started getting spammed with logger messages "Instances should only be created for meshes with geometry."

All meshes and rootNodes(probably the logger cause) added by instantiateModelsToScene now tagged as "isAnInstance" when running the following code in console

scene.meshes.forEach( (mesh) => {
    console.error(mesh.name, mesh.isAnInstance)
})

and animations can no longer be played separately,

check console (might need to hard reload), should show the logger message spam, the heads are also supposed to move/animate independently of each other (delayed), check the 4.2.1 bjs version as reference
https://playground.babylonjs.com/#S7E00P