Historical block hash support

[bilyana-gospodinova]

Problem

As part of the implementation of modularized services we came into the issue that only the last 256 block hashes can be read (this comes from the hedera.app dependency). The mirror node needs to return the block hash of any block.

Solution

We need to adjust the state to return any block hash. Might need to replace the singleton logic with KV.

Alternatives

No response