A document template describe what are the tags that the signature system will search on the document to apply the signing markers that the signer can then check to apply the signature during the call.
Bear in mind that you cannot use the same tag twice on the same template.
This end-point can be used to create a template for a document to sign. The
sign_coordinates array contains the list of tags that must be in the pdf uploaded during the call.
y offsets allow to align the signature in the final signed document.