HPCC-31559 Add option to avoid renames (spray and thor for now)

[jakesmith]

Introduce an option expert/avoidRename that components can use to avoid writing to a temp file, and renaming, and instead write directly to the target filename.
This is an experiment in relation to HPCC-31427.

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Testing:

[github-actions]

Jira Issue: https://hpccsystems.atlassian.net//browse/HPCC-31559

Jirabot Action Result:
Workflow Transition: Merge Pending
Updated PR
Assigning user: [email protected]

[jakesmith]

@ghalliday @mckellyln - please review.

NB: I haven't been able to properly test the spray side on k8s (local machine problems)., but believe it's correct

[mckellyln]

very minor, could check atomic value again after getting lock.

[mckellyln]

Looks ok to me.
But I don't know the details and implications elsewhere of going down this direct file write path.
One minor comment.

[mckellyln]

Approved.
Good to squash.

[jakesmith]

@ghalliday @mckellyln - please review.

NB: I haven't been able to properly test the spray side on k8s (local machine problems)., but believe it's correct

I have now tested spraying with the option on in k8s.

[ghalliday]

@jakesmith how about thindexwriteslave.cpp(~214)?

[jakesmith]

@jakesmith how about thindexwriteslave.cpp(~214)?

createWriteMultiple (called on 215) is where the option is used and the flags are manipulated, so this case is covered as well.