CNDB-14361 use node's total document and term counts (#1791)

[driftx]

What is the issue

BM25 score needs to use document average length aggregated on entire node.
Also a bug was discovered, which was introduced by #1789: term frequencies don't
include documents filtered by other predicates, which makes inconsistent result
between query plans.

What does this PR fix and why was it fixed

Fixes https://github.com/riptano/cndb/issues/14361

Changes that BM25 score uses document count and term count aggregated on entire node instead of per segment. Fixes a bug in calculating term frequencies, so
they count all documents.

As the work added more code duplication all duplicated code is refactored in getTopKRows methods.

In addition removes unnecessary public modifier in afffected interface.

[github-actions]

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
• All new files should contain the DataStax copyright header instead of the Apache License one

[driftx]

Clean merge.

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
93.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[cassci-bot]

❌ Build ds-cassandra-pr-gate/PR-1877 rejected by Butler

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33 new test failure(s) in 2 builds
See build details here

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Found 33 new test failures

Showing only first 15 new test failures

Test	Explanation	Branch history	Upstream history
...lidation.operations.AlterTest-compression_jdk11	regression	🔴🔴
t.TestCqlshUnicode.test_unicode_identifier	regression	🔴🔵
...nQueryShouldNotTimeoutWhenItExceedesReadTimeout	regression	🔴🔴
...nglePageReadIsFastButAggregationExceedesTimeout	regression	🔴🔴
...estInterruptedExceptionCachedCounterLockManager	regression	🔴🔵
...adCommitLogAndSSTablesWithDroppedColumnTestCC50	regression	🔴🔴
...oadCommitLogAndSSTablesWithDroppedColumnTestDSE	regression	🔴🔴
...thRestartTest.testReadingValuesOfDroppedColumns	regression	🔴🔴
o.a.c.d.t.s.f.FeaturesVersionSupportDBTest.testANN	regression	🔴🔴
o.a.c.d.t.s.f.FeaturesVersionSupportDCTest.testANN	regression	🔴🔴
o.a.c.d.t.s.f.FeaturesVersionSupportEBTest.testANN	regression	🔴🔴
...c.FeaturesVersionSupportTest.testANNSupport[eb]	regression	🔴🔴
....FeaturesVersionSupportTest.testGeoDistance[aa]	regression	🔴🔴
....FeaturesVersionSupportTest.testGeoDistance[ba]	regression	🔴🔴
...cySSTableTest.testVerifyOldDroppedTupleSSTables	regression	🔴🔴

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Found 1 known test failures