Gets a list of the user's transactions that match the provided list of Akahu transaction identifiers.
The intended use for this endpoint is to assist in 📖 transaction webhooks.
When a webhook arrives it contains a list of changed transaction identifiers, which you can simply pass unchanged to this endpoint to retrieve the full transactions.
This endpoint is unusual, in that it is really a GET, dressed up as a POST.
The reason we do this is to avoid having to put all of the IDs in query parameters, which could potentially come up against maximum URL length constraints.
Transactions will look different depending on your app's permissions.