Allow updates of user information from Sunshine to Zendesk

Feature Request Summary: 

For Sunshine integrations, allow user information (specifically the "Social Messaging User Info" field) to update over time in Zendesk.  Today, it is only populated upon creation of the initial ticket, and updates are not possible.

Description/Use Cases: 

For mobile app integrations using Sunshine, we leverage a "Social Messaging User Info" field which is populated with useful information about the user that we want our agents to know about the user as they respond to a user message.  Our app populates this information through an API update to Sunshine, which passes this information along to Zendesk when a new ticket is created.  Our agents can then review the information about the user in the Zendesk portal and consider this information when responding.  Unfortunately, even though our mobile app will update Sunshine whenever information about a user changes, this data is only sent to Zendesk upon the initial ticket creation - thus updates over time are not supported. 

We need updates over time because the richness of the data we provide in this field to our agents is crucial in them providing a good response to the end user who may be asking additional follow-up questions over time (hopefully over a period of many weeks or months for an engaged user).

Business impact of limitation or missing feature:

This is critical for our business as our agents do not have the latest key user information to understand the user's ever changing information - in our case this includes goals and concerns that the user has and is trying to address through continued use of our app.

Other necessary information or resources:

This was originally raised as a support ticket #9974248, but I was directed by the support team to raise this as a product enhancement request instead.