public Activity()
 {
     PreviousOperationDates = new OperationDates();
     ChildAgeAndGradeCalculationOperation = new ActivityChildAgeAndGradeCalculationOperation();
     NewRegistrationSyncOperation         = new ActivitySyncOperation();
     CoreContactAttributeSyncOperation    = new ActivitySyncOperation();
     ChildAgeAndGradeSyncOperation        = new ActivityChildAgeAndGradeSyncOperation();
     ActivityProgress = new ActivityProgress();
 }
 public Activity(DateTime executionStartTime)
 {
     Execution = new ExecutionTime(executionStartTime);
     Id        = $"{nameof(Activity)}_{Execution.StartUtc:u}"; // ISO8601: universal/sortable
     PreviousOperationDates = new OperationDates();
     ChildAgeAndGradeCalculationOperation = new ActivityChildAgeAndGradeCalculationOperation();
     NewRegistrationSyncOperation         = new ActivitySyncOperation();
     CoreContactAttributeSyncOperation    = new ActivitySyncOperation();
     ChildAgeAndGradeSyncOperation        = new ActivityChildAgeAndGradeSyncOperation();
     ActivityProgress = new ActivityProgress();
 }