Support AccessibilityInfo.isBoldTextEnabled and boldTextChanged on Android

[camilopires]

Summary:

On Android, AccessibilityInfo.isBoldTextEnabled() always resolves to false, and boldTextChanged never fires. Android 12 (API 31) added a Bold Text setting, exposed as Configuration.fontWeightAdjustment. Apps currently can't detect it, even though it changes text layout (for example #54931).

This reads fontWeightAdjustment on Android 12 and later and treats a positive adjustment as Bold Text. A negative value means lighter text, and FONT_WEIGHT_ADJUSTMENT_UNDEFINED means the value isn't known; neither counts. The module listens for configuration changes while the app is resumed, reads the value again on resume, and emits boldTextChanged. On Android versions before 12, the method still resolves to false. If the native module predates this change, isBoldTextEnabled still resolves to false rather than rejecting.

RNTester now shows the Bold Text examples on Android.

Discussion: react-native-community/discussions-and-proposals#477

Changelog:

[ANDROID] [ADDED] - AccessibilityInfo.isBoldTextEnabled() and boldTextChanged now work on Android 12 and later

Test Plan:

• yarn jest packages/react-native/Libraries/Components/AccessibilityInfo: all tests pass
• yarn flow-check: 0 errors
• yarn lint: passes
• yarn build-types --validate: API snapshot up to date
• yarn test-generated-typescript and yarn test-typescript-legacy: pass
• yarn format-check-kotlin: passes
• ./gradlew :packages:react-native:ReactAndroid:testDebugUnitTest --tests "com.facebook.react.modules.accessibilityinfo.*": 4 new tests pass, covering adjustments of 300, 0, -100 and undefined

RNTester on an Android 16 (API 36) emulator, Accessibility → "Check if the display options are enabled":

• adb shell settings put secure font_weight_adjustment 300 → "Bold Text is enabled."
• … 0 → "Bold Text is disabled."
• … -100 (lighter text) → "Bold Text is disabled."
• Live event without activity recreation. I temporarily added fontWeightAdjustment to RNTester's configChanges, locally and not in this PR, so the activity isn't recreated. Switching 0 → 300 → 0 updated the row in place in the same process.
• Changed while in the background: set 300, then brought the app back. The row showed "enabled" in the same process.

RNTester on an Android 10 (API 29) emulator: the row shows "Bold Text is disabled." even with the setting at 300, and there were no crashes across launch and resume.

Not run: Android 12–13 (API 31–33) devices. The SDK_INT guard covers them.

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Warning

JavaScript API change detected

This PR commits an update to ReactNativeApi.d.ts, indicating a change to React Native's public JavaScript API.

• Please include a clear changelog message.
• This change will be subject to additional review.

This change was flagged as: POTENTIALLY_BREAKING

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