[Access Node] Add field to access api reponses indicating what the latest block height was on the node

[peterargue]

Problem Definition

When querying an Access Node for data, there's no way to know what the current protocol state is for the AN you are interacting with. This can make it difficult to know if the results you get from some queries are due to the AN being behind or the actual state. e.g. querying Transaction results or latest sealed block.

Proposed Solution

Include in all Access API responses a field that indicates the latest finalized block height. This height can then be used by clients as a reference when processing the response