[Backport 2.x] Star tree codec changes

[opensearch-trigger-bot]

Backport f0c2fa6 from #14514.

[github-actions]

❌ Gradle check result for 12d9c7c: FAILURE

Please examine the workflow log, locate, and copy-paste the failure(s) below, then iterate to green. Is the failure a flaky test unrelated to your change?

[github-actions]

❌ Gradle check result for 12d9c7c: FAILURE

Please examine the workflow log, locate, and copy-paste the failure(s) below, then iterate to green. Is the failure a flaky test unrelated to your change?

[github-actions]

✅ Gradle check result for 12d9c7c: SUCCESS

[codecov]

Codecov Report

Attention: Patch coverage is 87.91209% with 11 lines in your changes missing coverage. Please review.

Project coverage is 71.53%. Comparing base (cfd427a) to head (12d9c7c).
Report is 2 commits behind head on 2.x.

Files	Patch %	Lines
...ec/composite/datacube/startree/StarTreeValues.java	0.00%	4 Missing ⚠️
...ex/codec/composite/Composite99DocValuesWriter.java	92.10%	0 Missing and 3 partials ⚠️
...ex/codec/composite/Composite99DocValuesFormat.java	80.00%	2 Missing ⚠️
...ex/codec/composite/Composite99DocValuesReader.java	85.71%	2 Missing ⚠️

Additional details and impacted files

@@             Coverage Diff              @@
##                2.x   #15376      +/-   ##
============================================
- Coverage     71.59%   71.53%   -0.06%     
+ Complexity    63108    63078      -30     
============================================
  Files          5173     5179       +6     
  Lines        296034   296120      +86     
  Branches      43114    43121       +7     
============================================
- Hits         211931   211826     -105     
- Misses        66334    66545     +211     
+ Partials      17769    17749      -20     

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