Bulk helper should instrument entire operation

The Bulk helper can issue multiple requests behind the scenes if requested. In this case we should instrument the entire operation as a single action in addition to the underlying scan/bulk request actions.

Locate the Bulk helper and the existing instrumentation for its underlying scan/bulk request actions. Confirm how a multi-request operation is represented, then make the whole Bulk operation emit one additional action while preserving the underlying actions.

索引モデルが issue の本文から書いたものです。