[DavidEichmann] Add ledger configuration node-to-client query

[nfrisby]

Key changes:

• Add GetLedgerConfig :: Query blk (LedgerConfig blk)
• Make SerialiseNodeToClient blk (LedgerConfig blk) a superclass of SerialiseNodeToClientConstraints
  • This makes sense now that the Node-to-Client protocol includes a GetLedgerConfig query.
• Add CBOR serialization instances for ledger configs and nested types.

[nfrisby]

This is merely a migration of https://github.com/input-output-hk/ouroboros-network/pull/3214.

In particular, that PR ^^^ has literally 100+ comments that might be of interest to you :'(

The rebased involved tedious conflicts. I deferred them by merely adding them to the content of the commits!