HPCC-32946 Capture and report lookahead timings for hash distributor

[shamser]

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[github-actions]

Jira Issue: https://hpccsystems.atlassian.net//browse/HPCC-32946

Jirabot Action Result:
Workflow Transition To: Merge Pending
Updated PR

[jakesmith]

I don't think this is right, the stream it's counting lookahead time may be the input that you want to count look ahead time, but createHashDistributor could be distributing anything, it's a general utility.

It would better to count the time it spent reading it's input, then let the calling activity gather it's time if it needed to.

[shamser]

@jakesmith None of the code from the earlier PR remains, so I haven't retained the earlier commit in this PR.

[jakesmith]

@shamser - please see comments

[jakesmith]

@shamser - looks good. Please squash