Fix stale Fabric sticky header measurements after unsticking

[adamhari]

Summary:

Issue #51911 reports that measure and measureInWindow return the original y coordinate while an iOS Fabric sticky header is visibly stuck. On current main, the native interpolation listener needed to mirror the sticky translation into Fabric was restored by #58037. That earlier change addresses the reported sticky-state failure; this PR does not reimplement it.

This PR covers the sticky header's native event path and fixes a remaining stale measurement when the header returns to its layout position. ScrollViewStickyHeader currently ignores the first zero from every interpolation listener. After a nonzero sticky translation, a later zero is a real position update. Scope the initial-zero guard to each new interpolation so that later zero reaches the Fabric shadow tree. The regression test sends native interpolation updates for initial zero, sticky translation, and return to zero, then checks the explicit transform that Fabric uses for measurement.

Related to #51911. Depends on the listener behavior restored in #58037.

Changelog:

[GENERAL] [FIXED] - Keep Fabric sticky header measurements in sync when a header returns to its layout position.

Test Plan:

• corepack yarn test packages/react-native/Libraries/Components/ScrollView/__tests__/ScrollViewStickyHeader-test.js --runInBand --silent — passed (1 test).
• corepack yarn flow-check — passed (0 errors).
• corepack yarn eslint --max-warnings 0 packages/react-native/Libraries/Components/ScrollView/ScrollViewStickyHeader.js packages/react-native/Libraries/Components/ScrollView/__tests__/ScrollViewStickyHeader-test.js — passed.
• corepack yarn prettier --check packages/react-native/Libraries/Components/ScrollView/ScrollViewStickyHeader.js packages/react-native/Libraries/Components/ScrollView/__tests__/ScrollViewStickyHeader-test.js — passed.
• git diff --check — passed.
• iOS Fabric manual check remains: run the reproducer from measurement y values for nodes used in stickyHeaderIndices do not match it's sticky positioning #51911, scroll until the header sticks, measure with measure and measureInWindow, then scroll back and measure again. Compare the reported coordinates with the visible header and capture a video. I could not run this check or capture a video on this Windows host without Xcode or an iOS simulator.

[meta-cla]

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