fn validate_chat_session_update(
old_profile_key: Option<&ProfilePublicKeyData>,
new_session: RemoteChatSessionData,
profile_id: Uuid,
validator: Option<&dyn SignatureValidator>,
) -> ChatSessionUpdateOutcomefn validate_chat_session_update(
old_profile_key: Option<&ProfilePublicKeyData>,
new_session: RemoteChatSessionData,
profile_id: Uuid,
validator: Option<&dyn SignatureValidator>,
) -> ChatSessionUpdateOutcome