Receive multipart/form-data POST and trigger DOI-Request in Send-dApp directly

Current Situation: A website user enters its data and email address into a form which is sent to an application server. This application server takes this information and reformats it into an REST-API call to Send-dApp opt-in in order to start the doi request process on doichain.

Enhancement: It would be possible to reduce this workflow one step1 so the Send-dApp directly can receive a multipart-formdata POST from a defined referrer.

Here it is necessary ot combine the RPC-API call with a captcha which was created before it was called.