Timeline for implementing KHR_interactivity?

Hi, I am an engineer at Google working on [Geospatial Creator](https://developers.google.com/ar/geospatialcreator/unity). We are considering integrating with UnityGLTF to enable cross-platform portability of AR scenes with the GLTF format. We’d like to eventually support the `KHR_interactivity` extension, so I’m curious if that extension is on your roadmap for UnityGLTF and, if so, what the timeline for that looks like?

CC: @elalish who is also working on this effort on the Google side.

Start by reviewing the KHR_interactivity extension requirements and UnityGLTF's existing extension support. Determine whether implementing the extension is within the project's roadmap, define the required UnityGLTF scope, and establish how support would be validated for portable AR scenes.

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