feat(gitops-engine): show and format detailed field changes in StatefulSet immutable field errors

[aali309]

Fixes: #21209
Part of: #21209
Replaces: argoproj/gitops-engine#654

This PR Improves error messages when attempting to modify immutable fields in StatefulSets by showing exactly which fields changed and their before/after values.

Checklist:

• Either (a) I've created an enhancement proposal and discussed it with the community, (b) this is a bug fix, or (c) this does not need to be in the release notes.
• The title of the PR states what changed and the related issues number (used for the release note).
• The title of the PR conforms to the Title of the PR
• I've included "Closes [ISSUE #]" or "Fixes [ISSUE #]" in the description to automatically close the associated issue.
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Before the change:

After the change:

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 62.44%. Comparing base (e77acec) to head (63422cc).
⚠️ Report is 583 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master   #25171      +/-   ##
==========================================
- Coverage   62.44%   62.44%   -0.01%     
==========================================
  Files         351      351              
  Lines       49463    49463              
==========================================
- Hits        30888    30885       -3     
- Misses      15609    15614       +5     
+ Partials     2966     2964       -2     

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[github-actions]

This pull request has been marked as stale because it has had no activity for 90 days. Please comment if this is still relevant.