CNDB-12308: Remove index-based sorting at CQL level

[adelapena]

It was recently found that index-based sorting is done twice in the coordinator. The first sorting is done by StorageAttachedIndexQueryPlan#postProcessor, at the service level, which sorts a PartitionIterator. Then a second sorting is done by SortedRowsBuilder, at the CQL level, which sorts a simpler List<ByteBuffer>.

CNDB-11762 removed the entire StorageAttachedIndexQueryPlan#postProcessor method so sorting was not duplicated anymore. However, this was problematic for implementations of QueryInfoTracker.ReadTracker, which is applied after sorting with the postprocessor, but before sorting at the CQL level, here. Thus, that change was reverted to avoid breaking external trackers relying on the previous behaviour.

I think what we should do instead is to get rid of index-based sorting at the CQL level, so all sorting is done by the postprocessor. The postprocessor works at a lower level so, with some adjustments, it should be able to do all the sorting on its own without needing CQL intervention. That should remove the duplicated sorting and simplify CQL a bit.

Checklist before you submit for review

• Make sure there is a PR in the CNDB project updating the Converged Cassandra version
• Use NoSpamLogger for log lines that may appear frequently in the logs
• Verify test results on Butler
• Test coverage for new/modified code is > 80%
• Proper code formatting
• Proper title for each commit staring with the project-issue number, like CNDB-1234
• Each commit has a meaningful description
• Each commit is not very long and contains related changes
• Renames, moves and reformatting are in distinct commits

[adelapena]

@michaeljmarshall could you please review this one?

[sonarqubecloud]

Quality Gate passed

Issues
2 New issues
0 Accepted issues

Measures
0 Security Hotspots
93.2% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[cassci-bot]

❌ Build ds-cassandra-pr-gate/PR-1488 rejected by Butler

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4 new test failure(s) in 4 builds
See build details here

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Found 4 new test failures

Test	Explanation	Branch history	Upstream history
...ToolEnableDisableBinaryTest.testMaybeChangeDocs	regression	🔴🔵🔴🔴	🔵🔵🔵🔵🔵🔵🔵
...ap<float,float>,wide=true,scenario=MIXED_QUERY]	regression	🔴🔵🔵🔵	🔵🔵🔵🔵🔵🔵🔵
...>,wide=false,scenario=POST_BUILD_QUERY]	regression	🔴🔵🔵🔵	🔵🔵🔵🔵🔵🔵🔵
...n.ConnectionTest.testMessageDeliveryOnReconnect	regression	🔴🔵🔵🔵	🔵🔵🔵🔵🔵🔵🔵

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Found 10 known test failures