Backport recent changes from polkadot staging (#2590)

* fiox overflow when computing priority boost (#2587)

* Backport changes from polkadot-sdk (#2588)

* backport https://github.com/paritytech/polkadot-sdk/pull/1543

* another backport

* https://gitlab.parity.io/parity/mirrors/polkadot-sdk/-/jobs/3833103