Ktx2 integration

[HerbRrosemary]

ktx2.0测试

[cesium-concierge]

Thank you so much for the pull request @HerbRrosemary! I noticed this is your first pull request and I wanted to say welcome to the Cesium community!

The Pull Request Guidelines is a handy reference for making sure your PR gets accepted quickly, so make sure to skim that.

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[ebogo1]

Hi @HerbRrosemary, this appears to be a duplicate of the original KTX 2.0 PR (#9040), which was closed. The effort is now being continued in #9513.