[Event log] Update findEventsBySavedObjectIds to resolve SO ids

[chrisronline]

As part of the research done in #100666, we need to update the findEventsBySavedObjectIds client API method to properly resolve saved object ids. This API already makes use of the current space so it should be relatively easy to change.

One slight complication here is using the appropriate space for saved object id resolution, as the caller's space might differ from the namespace defined in the event log itself.

I don't expect this part of the code to need to worry about how to handle possible responses from the .resolve() API, but rather just use it to ensure we fetch the correct saved object.

For reference, here is a PoC commit (part of the overall PoC) of how we might do this.

[elasticmachine]

Pinging @elastic/kibana-alerting-services (Team:Alerting Services)

[chrisronline]

I'm going to close this out, as the original research is invalid and need to be reworked. If this item is still applicable, we still reopen this ticket.