[FEAT] - Add Functionality to Query Full Block Details by Hash

[CarlosLopezDeLara]

Internal/External
Internal

Describe the feature you'd like
Provide a mechanism, accessible via Node-to-Client to query the Cardano node for detailed information about a specific block using its hash.

Motivation:

Currently, developers and builders (such as those behind cardanoscan.io, typhonwallet.io, and potentially DEXs) desire a more direct way to retrieve block data from the node than relying on tools like db-sync.

This functionality would mirror capabilities found in other blockchains, such as Bitcoin's getblock RPC call, making development and block exploration more straightforward.

The need exists to query both historical blocks and the current chain tip.

Desired Information (Output):

Given a block hash, the query should return comprehensive block details, including (but not limited to):

Transactions within the block
Slot number
Previous block hash
Block depth (confirmation count)
Block size

Previous discussions:

@jasagredo suggested that the most viable node-based solution appears to be exposing the existing BlockFetch protocol (currently used for Node-to-Node communication - NTN) through the Node-to-Client (NTC) interface

Rationale: BlockFetch already interacts with the immutable database (which acts as the necessary index) to retrieve blocks. Exposing it via NTC would allow trusted local clients to request specific blocks directly, potentially simplifying implementation compared to NTN which involves inter-node trust assumptions.

This would be complemented by native RPC implementation described in IntersectMBO/cardano-node#6185 and also through API and CLI

Additional context / screenshots

• https://developer.bitcoin.org/reference/rpc/getblock.html|

• Originally requested by [FR] - need cli query to fetch a specific transaction and block cardano-node#6121