feat(yoga): Add cache miss tracking to LayoutData for hit rate metrics

[zubeyralmaho]

PR: feat(yoga): Add cache miss tracking to LayoutData for hit rate metrics

Summary

Add layoutCacheMisses and measureCacheMisses fields to Yoga's LayoutData struct to enable cache hit rate calculation in layout performance analysis.

Currently, Yoga tracks cache hits (cachedLayouts, cachedMeasures) but not cache misses. This makes it impossible to calculate cache efficiency metrics like hit rate percentage.

With this change, consumers of the LayoutPassEnd event can now compute:

float layoutHitRate = (float)cachedLayouts / (cachedLayouts + layoutCacheMisses);
float measureHitRate = (float)cachedMeasures / (cachedMeasures + measureCacheMisses);

This enables better performance profiling and optimization insights for React Native apps.

Changelog: [INTERNAL] [ADDED] - Add cache miss tracking to Yoga LayoutData for hit rate metrics

Test Plan

• Built Yoga library successfully with cmake and make
• Verified first layout produces cache misses (2 misses for root + child nodes)
• Verified second layout with same dimensions produces cache hits (1 hit)
• Verified cache hit rate is calculable (100% on second pass with same dimensions)

Testing cache hit/miss metrics...
After first layout:
  cachedLayouts: 0
  layoutCacheMisses: 2
  ✓ First layout has expected cache misses

After second layout (same dimensions):
  cachedLayouts: 1
  layoutCacheMisses: 0
  ✓ Second layout has expected cache hits

Layout Cache Hit Rate: 100%
✅ All cache metrics tests passed!

Impact

• No breaking changes
• Backward compatible (new fields default to 0)
• Minimal performance overhead (single integer increment per layout operation)

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[react-native-bot]

This PR is stale because it has been open for 180 days with no activity. It will be closed in 7 days unless you comment on it or remove the "Stale" label.

[react-native-bot]

This PR was closed because it has been stalled for 7 days with no activity.

[react-native-bot]

This PR was closed because it has been stalled for 7 days with no activity.