It would be useful to include the context.Context in the CommandStartedEvent and CommandFinishedEvent structs so extra application contextual information can be included in metrics. Things such as the calling function or the source of the query would be great to include in our metrics but right now there's no way to connect these events to their original function calls. If the context was passed along then a value could be added to the context and then retrieved later from the event.

I would be willing to contribute these changes if this is an acceptable feature. I would add a `Ctx context.context` field to `CommandStartedEvent` and `CommandFinishedEvent`.