Companion for pallet-mmr: generate historical proofs (#6061)

* BEEFY: generate historical proofs

Signed-off-by: Serban Iorga <[email protected]>

* cargo update -p sp-io

* Properly set max proof size for runtimes

* Properly set max proof size for mocks

* cargo fmt

* Set appropriate UMP service total proof size weight

* Disable zombienet-tests-parachains-disputes CI

* Add comment explaining weight math

* Use MAX_POV_SIZE for max proof size

* Cast to u64

* Remove comment

Signed-off-by: Serban Iorga <[email protected]>
Co-authored-by: Keith Yeung <[email protected]>