As an AppExchange App developer, I want to be able to create an email service in user's (installer) org when they configure or install my app. I have looked into SOAP API for Partners but have found nothing yet.
Please note that I am aware that currently it is not possible to create Email Service (i.e. EmailServicesFunction record) via Apex. The question is about how to create it via APIs other than Apex such as SOAP, Rest and/or Metadata API.
Could you please help me with which API would allow me to do that and an examples you could provide?