Add Trusted Signals KVv2 support to W3C Spec (#1340)

* Add Trusted Signals KVv2 support to W3C

* Add Trusted Signals KVv2 support to W3C

* Apply suggestions from code review

Co-authored-by: qingxinwu <6334674+qingxinwu@users.noreply.github.com>

* Apply suggestions from code review

* Apply suggestions from code review

* Add struct for compressiong group and partition

* Add struct for compressiong group and partition

* Update spec based on comments and suggestions

* Add Trusted Signals KVv2 support to W3C Spec

* Add Trusted Signals KVv2 support to W3C Spec

* Use map set in proper positions

* Update spec based on comments and suggestions

* Update spec based on comments and suggestions

* Update spec based on comments and suggestions

* Update spec based on comments and suggestions

* Update spec based on comments and suggestions

* Update spec.bs

* Apply suggestions from code review

Co-authored-by: Paul Jensen <JensenPaul@users.noreply.github.com>

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Co-authored-by: Tianyang Xu <xtlsheep@google.com>
Co-authored-by: qingxinwu <6334674+qingxinwu@users.noreply.github.com>
Co-authored-by: Paul Jensen <JensenPaul@users.noreply.github.com>

Author: 4 people