CNDB-17012: Improve TrieMemoryIndex row count estimation

[pkolaczk]

Fixes a bug in TermsDistribution#toBigDecimal which didn't preserve
order for some types and broke the assertion
in TrieMemoryIndex#estimateNumRowsMatchingRange.

Additionally, replaces the row count estimation algorithm with a better
one:

• simpler
• more efficient (no need to search and iterate the trie)
• more accurate (especially for wider ranges)

[github-actions]

Checklist before you submit for review

• This PR adheres to the Definition of Done
• 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

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
93.5% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[adelapena]

LGTM. I would only add a comment on the new test about the limitations of the algorithm, basically what is said by this comment: #2262 (comment)

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
93.5% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[cassci-bot]

❌ Build ds-cassandra-pr-gate/PR-2262 rejected by Butler

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4 regressions found
See build details here

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Found 4 new test failures

Test	Explanation	Runs	Upstream
o.a.c.distributed.test.AbortedQueryLoggerTest.testLogsReadMetrics	REGRESSION	🔴🔴	0 / 30
o.a.c.index.sai.cql.VectorCompaction100dTest.testCompactionWithEnoughRowsForPQAndDeleteARow[version=ec enableNVQ=true]	REGRESSION	🔴⚪	0 / 30
o.a.c.index.sai.cql.VectorKeyRestrictedOnPartitionTest.partitionRestrictedWidePartitionPqCompressedTest[version=ca enableNVQ=false enableFused=false]	REGRESSION	🔴⚪	0 / 30
o.a.c.index.sai.cql.VectorSiftSmallTest.testMultiSegmentBuild[version=ed enableNVQ=true enableFused=false]	REGRESSION	🔴🔴	0 / 30

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Found 7 known test failures