Make Controller log and Agent log available to JOC Cockpit

Current Situation

• When Controller and Agent raise errors in response to user instructions then errors and warnings are reported back to JOC Cockpit by use of events.
• This does not apply to errors and warnings that are caused by autonomous operations. For example, in case that a monitored directory is missing or becomes unavailable the Agent will raise an error that is visible from the Agent's log file only.

Desired Behavior

• The logs of Controller and Agent should be reported back to JOC Cockpit.
• The JOC Cockpit Log Service will request the Controller to report back
  • the current log files of Controller and Agents: this boils down to report the current controller.log and agent.log files.
  • log entries from deltas: the JOC Cockpit Log Service keeps track of the point in time when log entries have been requested. The Controller will report back log entries that are newer than the given timestamp. The Log Service will perform such requests in a configurable interval, for example every 2 minutes,
• If Agents are not reachable then the Controller will add this information to its response to the Log Service.
• Reporting of logs is considered a continued task. This is not related to roll-over of log files for example on change of day.