CNDB-15759: add unified_compaction.scaling_parameter_persistence flag

[driftx]

What is the issue

Unified compaction write a json representation of the scaling parameters. There should be a way to disable this.

What does this PR fix and why was it fixed

Adds a unified_compaction.scaling_parameter_persistence flag which defaults to true.

[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
100.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[cassci-bot]

❌ Build ds-cassandra-pr-gate/PR-2082 rejected by Butler

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3 regressions found
See build details here

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Found 3 new test failures

Test	Explanation	Runs	Upstream
o.a.c.db.ColumnFamilyStoreTest.testDiscardSSTables	REGRESSION	🔴⚪	0 / 13
o.a.c.index.sai.cql.VectorCompaction100dTest.testOneToManyCompaction[ec false]	REGRESSION	🔴⚪	0 / 13
o.a.c.index.sai.cql.VectorSiftSmallTest.testRerankKZeroOrderMatchesFullPrecisionSimilarity[ed false false]	REGRESSION	🔴⚪	0 / 13

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Found 2 known test failures