Index builds emit metrics for in-progress index builds, however we should also track (using an OTel histogram) the overall duration of the index build, as well as attributes indicating the phase it was started from (either "initialized" or the resumed phase, if resumed) and the outcome (success, failure, or "to be resumed").

This should be accompanied by a (potentially refactored) log message that is emitted for all index builds, along with the index build UUID and collection UUID (and/or other identifying attributes).

The best place to do this may be in ActiveIndexBuilds::unregisterIndexBuild(..), in order to track all index builds as they terminate.