Adding support for messageType in sms

## What are the schemas that are affected by the issue
https://github.com/adobe/xdm/blob/master/docs/reference/adobe/experience/customerJourneyManagement/messageprofile.schema.json
https://github.com/adobe/xdm/blob/master/docs/reference/adobe/experience/customerJourneyManagement/message-delivery-feedback.schema.json

## What are examples of products that are impacted by the issue
What are examples of products that are impacted by the issue
AJO (Adobe Journey Optimizer)

Start by reading the linked messageprofile.schema.json and message-delivery-feedback.schema.json files, then inspect how the XDM schemas represent SMS message fields for Adobe Journey Optimizer. The issue does not define the messageType values or expected schema changes; done criteria would need to confirm the intended representation in both affected schemas.

Written by the indexing model from the issue text.