How to Upload and Manage Templates in ServiceM8 Using API?

I need to upload an updated document template into the ServiceM8 template directory programmatically. I found the following API endpoint in the documentation:

Produce a Templated Document
POST https://api.servicem8.com/platform_produce_document

This endpoint allows combining objects with document templates to produce output in formats like PDF, DOCX, or JPG. However, it seems to only download the generated documents using existing templates.

Is there any way to upload or update templates in ServiceM8 using their API? If not, what is the best workaround to automate template management?