How should the other processes try to recreate Zebra's non-finalized best chain when using the ReadStateService

[arya2]

We want a way to keep up with the latest non-finalized blocks in Zebra's best chain from other processes for the RPC wallet.

It may be possible to do this using the get_best_block_hash and get_block RPC methods. See the example code here in the has_non_finalized_best_chain fn for an idea of how this could be implemented.