Feature Request: Allow Lights Agents to be CC'd as regular users

Feature Request Summary: 

Allow Light Agents to be cc'd as a Customer, see all previous comments in a ticket, and respond as an agent via Public response.

Description/Use Cases: 

We have several specific forms used for processes that would help have this feature. For example:

1. The district utilizes Zendesk for a public Incident Request form for Bullying, harassment, etc... This form is then sent to a shared email Support Agent but also adds the principals and Associate principals as light agents for notification and processing. If another teacher, parent, or student is cc'd on the ticket, the principal needs to notify them of their progress.

The business impact of limitations or missing features:

Notices from the principal are being missed by the requester since they were internal notes. Tickets are being missed in the system since the response is only internal.

Other necessary information or resources:

An alternative would be to allow Triggers, Automation, and Macros to add specific users as cc or requester.

Related but different: https://support.zendesk.com/hc/en-us/community/posts/4408868235802-Allow-light-agents-to-make-public-comments-on-their-requested-tickets?input_string=Feature%20Request%3A%20Allow%20Lights%20Agents%20to%20be%20CC%27d%20as%20regular%20users