Enable custom request AdditionaInstrumentationDetail

[idg10]

Menes calls IOperationsInstrumentation.StartOperation when invoking a service operation to ensure that applications that want telemetry will get clear information about when an operation starts and finishes, and that all other diagnostic telemetry produced while the operation runs is correlated with that operation.

Menes also passes an AdditionalInstrumentationDetail to StartOperation containing a single property, Menes.OperationId. This ensures that the operation is tagged with the operation ID. And if applications are using the Application Insights provide from Corvus.Monitoring, this property also flows to all correlated telemetry. This enables us to filter by operation ID, and see all telemetry corresponding to any particular OpenAPI operation.

Currently, there is no way for applications to add additional items to this per-operation detail. We have encountered scenarios in which applications want to add in extra, application-specific contextual information. Currently this is cumbersome because it needs to be added manually each time telemetry is generated. But if applications had a way to augment the detail passed to StartOperation, this manual effort could be avoided.

So we should consider adding something that enables applications to extend this information. E.g., an IOperationInstrumentationDetailBuilder.