Issue title: Node diagnostics - tequilapi api endpoint
 Issue body: Get events / metrics from SSO like structure and expose via tequilapi endpoint.

Part of https://github.com/mysteriumnetwork/node/issues/1386
 Comments: 
 Comment 0: This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

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