[iOS] Announce "collapsed" for aria-expanded={false} on New Architecture

[kimseongchan0914]

Summary:

Fixes #58746.

On iOS with the New Architecture, VoiceOver announces no state for an element with aria-expanded={false} (or accessibilityState={{expanded: false}}). For example, a collapsed accordion header is read as "Returns, button", so a VoiceOver user can't tell it apart from an ordinary button.

RCTViewComponentView added the "expanded" accessibility value only when expanded was true. There was no branch for false. The old-architecture RCTView announces both "expanded" and "collapsed", so this is a regression on the New Architecture.

This change adds the missing branch. It reuses the localized "collapsed" string that RCTView.m already uses. When expanded is unset, no state is added, as before.

Changelog:

[IOS] [FIXED] - VoiceOver now announces "collapsed" for aria-expanded={false} on the New Architecture

Test Plan:

Ran:

• npx clang-format on RCTViewComponentView.mm produced no diff
• git diff --check HEAD~1 HEAD was clean

Not run yet: an iOS build and a VoiceOver check on device. The expected VoiceOver output for <Pressable role="button" aria-expanded={...}> in RNTester (New Architecture) is:

aria-expanded	Before	After
false	"Returns, button"	"Returns, collapsed, button"
true	"Returns, expanded, button"	unchanged
unset	"Returns, button"	unchanged

🤖 Generated with Claude Code

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