Use LessThan here rather than Comparator for some key PriorityQueues

[thecoop]

Following from the regression identified in #14705 (comment), use LessThan rather than Comparator (which involves less function calls) for these key queues

[github-actions]

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[thecoop]

It is unclear which luceneutil commands the two performance tests can be run with, so I haven't been able to verify this fixed the performance drop locally.

[jpountz]

You need to add the nightly tasks which had a slowdown to your tasks file, e.g. here are the CountOrMany tasks: https://github.com/mikemccand/luceneutil/blob/main/tasks/wikinightly.tasks#L305-L309. Nightly benchmarks run with the wikibigall collection, but wikimedium10m or wikimediumall should be good too in order to confirm that performance gets better.

[thecoop]

This shows some improvement in those two tests - I say merge it and see what this and #14873 does

[jpountz]

This sounds good to me.

[thecoop]

Looks like this has improved performance back to what it was - https://benchmarks.mikemccandless.com/2025.07.01.18.04.59.html

[jpountz]

Thank you! I pushed an annotation.