Use `latest-transaction` endpoint to improve EB load

[tdroxler]

Currently the extension wallet is using /addresses/{address)/transactions?page=1&limit=1 every 5 minutes in background to check for new txs. Making that endpoint the most called in EB.

This would be more performant for EB to use the dedicated: /addresses/{address}/latest-transaction endpoint, which only return the overview info of the latest tx:

final case class TransactionInfo(
    hash: TransactionId,
    blockHash: BlockHash,
    timestamp: TimeStamp,
    coinbase: Boolean
)

But which is enough to know if it's a new one or not.

The issue with /addresses/{address)/transactions?page=1&limit=1 is that we are also querying inputs and outputs, while they are not needed in that context AFAIK.