NHS App API - allow push notification content to include the message sender name

The NHS App API offers an endpoint that allows the sending of an in-app message with an associated push notification.
https://digital.nhs.uk/developer/api-catalogue/nhs-app#api-Communication-create-in-app-with-notification

The content of this associated push notification can be configured on a per-App basis, but is otherwise static.

For consumers of the API who send in-app messages and push notifications on behalf of many different NHS Organisations (e.g. commissioned by many different GP surgeries), it would be beneficial if the associated push notification content could include the sender name field from the in-app message.

For example, such that the associated push notification title content could be configured to read "You have a new message from [sender name]", with the sender name token being dynamically replaced by the NHS App API when processing the request.