More ways to work with default automation user / rule actor - provide a functional only user that can be used for running automated process, ability to set "Run as Assignee" as the default automation executor

Problem Definition

as described on the following page automation can only be run as user who is defined as project default or a user who triggered the rule:
https://confluence.atlassian.com/servicedeskcloud/automating-your-service-desk-732528900.html

We currently created a user "Support Desk User" to trigger our rules.
We don´t want the assignee to be the trigger because we don´t want to confuse the customer with automatic comments.
They must see that this kind of comment is an automation.

Current Workaround
We created a new "Support Desk User" inside crowd and added him to a agent specific group.
Our way ends up in consuming one Agent license for automating comments and does not work as intended.

How do we use those automatic comments?

• As you can see in our example Workflow we have a step called Freezed.
• Behind this Freezed Status we have defined a SLA which counts 15 Business Days. After that this specific Issue will be "Reopened".
  That means it goes from "Freezed" -> "Waiting for Customer" -> "Waiting for Support"
  What we had here was a comment for the customer which said that this issue was unfreezed and that the support will stay in contact with the customer here. If this comment is provided by the "Support Desk User" the trigger will automatically move the issue back to "Waiting for Customer" because this rule was triggered by an agent.
  

Suggested Solution
Provide a functional only user or another way that can be used for running automation inside the Service Desk without consuming an agent license or the need of the assignee to trigger it.