Refactor FieldDataStats and CompletionStats with Builder pattern

[pado0]

Description

This PR refactors the FieldDataStats and CompletionStats class to use the Builder pattern instead of relying on multiple constructors.

By adopting the Builder pattern, it becomes easier to evolve the stats API, add new metrics, and maintain backward compatibility without forcing disruptive constructor changes.

Based on the related issue:

1. Added a Builder and deprecated the existing constructors.
2. Replaced usages of constructors in code and tests with the new Builder.

There are multiple stats-related classes that need similar refactoring, and we are addressing them in priority order. This PR covers FieldDataStats and CompletionStats as part of that effort.

Related Issues

Related to #19225

Check List

• Functionality includes testing.

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[github-actions]

❌ Gradle check result for 3e45413: FAILURE

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[github-actions]

❌ Gradle check result for 3e45413: null

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[github-actions]

❕ Gradle check result for 3e45413: UNSTABLE

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 73.21%. Comparing base (4dc8704) to head (0a65b90).
⚠️ Report is 4 commits behind head on main.

Additional details and impacted files

@@             Coverage Diff              @@
##               main   #19936      +/-   ##
============================================
- Coverage     73.25%   73.21%   -0.05%     
- Complexity    71555    71563       +8     
============================================
  Files          5785     5785              
  Lines        326828   326935     +107     
  Branches      47295    47295              
============================================
- Hits         239429   239365      -64     
- Misses        68163    68351     +188     
+ Partials      19236    19219      -17     

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[sandeshkr419]

Thanks for working on this. I have one method rename nit comment. Rest LGTM!

[github-actions]

✅ Gradle check result for 0a65b90: SUCCESS