Given a relay chain block, is there some way to construct a proving system for any connected parachain's state at that relay block?
I imaging there could be some information persisted on the relay that a(n archive) parachain node could be instructed to generate something like a vector commitment that anyone could verify out of band.
Meaning you could that a relay block + that commitment to verify a specific part of state for a parachain at that time.
Specifically a Substrate Devs chat member asked a question related to verifying state across parachains (on the same relay) is why I am asking here.