Updates #7573

The storage health check (check-storage subcommand of the util program) needs to be updated to support the new account status v4 format.

Account status v4 format was introduced by PR #7738.

After running migration, we should run storage health check. We should also run storage health check periodically on mainnet snapshots.

The last storage health check on testnet and mainet (account storage format v3) was today (Sept. 11, 2025) and no new problems were reported.