API get completion messages metadata

[myrtp]

• When semantic completion is conducted with rpovenAI enabled the Message entity is extended with the completioNMessageDTO to return information like: iscc codes, ownerName, embeddingModel.
• I want an API to return with the chat thread messages metadata (as described above)
• Handle the metadata depending on the attribution policy of proven ai data pods. if attribution policy = owner_name the name is returned, otherwise only the org name.