Tracking the snews_pt version

[KaraMelih]

As the snews_pt and snews_cs are developed in parallel, they need to be compatible.

if in the future, we make changes to snews_pt we will need to validate the messages generated by that version properly.

For this, we have introduced a schema_version field in the snews_pt with the idea that snews_cs checks the versioning and processes the message accordingly when consuming messages from the stream. However, we never implemented this check.