backport/rpc-v2: Implement `archive_unstable_storageDiff` (stable2412) #15096

Job	Run time
check-dependency-rules	9s
check-fail-ci	13s
check-markdown	14s
check-workspace	18s
preflight / preflight	40s
preflight / ci-versions	1m 25s
check-rust-feature-propagation	2m 8s
test-rust-features	2m 11s
check-toml-format	1m 2s
check-umbrella	2m 24s
fmt	1m 15s
All quick checks passed	1s
	12m 0s

Provide feedback