Remove the EnhancedJSONEncoder

[Christdej]

Describe the improvement you would like to see
There is a custom json encoder called EnhancedJSONEncoder, we should rather use pydantic models when we need to encode. This way we can get rid of the custom encoder.

How will this change existing functionality?
Strenghten and standardize json encoding before publishing messages

How will this improvement affect the current Threat Model?
Improve

[github-actions]

This issue has been automatically marked as stale due to inactivity.