V0 4 2 mfles agent fixes

Changes needed in Core following development of initial version of mFLES SCA (legacy compatibility mode)

• In Config Server add_tag, add agent to known agent list if yet unknown
• In ConfigCore, make get_known_agents and get_tags_list return tuple of success and list
• Unify clear_transitions_map of StateCoreAgent and local version in EcsCoreAgent