`JWK` is JSON objects representation of private, public, and secret keys ([docs](https://datatracker.ietf.org/doc/html/rfc7517)).
This allows transferring key between threads on Safari, structure clone algorithm should handle `JWK` format which is a simple JS object.
([context](https://linear.app/comm/issue/ENG-3872#comment-05084359))
Depends on D8118