feat: DH-18779: Auto-resize column header groups

[vbabich]

• Rebalance column header trees based on the width of columns and group names
• Add optional getMetricCalculator prop in IrisGrid and IrisGridPanel, needed to override metric calculator for Pivots
• Fix duplicated mouseHanders prop in the handlers array in IrisGrid, limit memoize to max: 1
• Fix missing expandDescendants parameter in toggleExpandColumn in IrisGrid

[codecov]

Codecov Report

❌ Patch coverage is 46.66667% with 56 lines in your changes missing coverage. Please review.
✅ Project coverage is 47.77%. Comparing base (b525cda) to head (c0d5e86).

Files with missing lines	Patch %	Lines
packages/iris-grid/src/IrisGridMetricCalculator.ts	20.00%	56 Missing ⚠️

Additional details and impacted files

@@                Coverage Diff                @@
##           release/v0.85    #2563      +/-   ##
=================================================
- Coverage          47.77%   47.77%   -0.01%     
=================================================
  Files                711      712       +1     
  Lines              39633    39732      +99     
  Branches            9902     9922      +20     
=================================================
+ Hits               18936    18982      +46     
- Misses             20684    20737      +53     
  Partials              13       13              

Flag	Coverage Δ
unit	47.77% <46.66%> (-0.01%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.
• 📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.