HPCC-32880 Ensure that legacy write costs are not lost after file read operation

[shamser]

Type of change:

• This change is a bug fix (non-breaking change which fixes an issue).
• This change is a new feature (non-breaking change which adds functionality).
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• This change is a breaking change (fix or feature that will cause existing behavior to change).
• This change alters the query API (existing queries will have to be recompiled)

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Testing:

[github-actions]

Jira Issue: https://hpccsystems.atlassian.net//browse/HPCC-32880

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

[AttilaVamos]

@shamser I think you need to rebase to fix that build problem.

[shamser]

@jakesmith I've rebased.