[Android] Set AccessibilityNodeInfo.stateDescription so TalkBack stops reading "checked. on." on switches

Description

On Android, a view with accessibilityRole="switch" and accessibilityState={{ checked: true }} is read by TalkBack as "checked. on.". TalkBack takes "on" from the Switch class name and "checked" from isChecked. It suppresses the generic word only when stateDescription is set (API 30+).

ReactAccessibilityDelegate.kt on main never calls setStateDescription: for STATE_CHECKED it sets only isCheckable and isChecked. No JS prop reaches stateDescription, so apps can't fix this without native code.

A related request, #34736 ("Custom State Descriptions"), was closed by the stale bot in 2023 without a PR.

Steps to reproduce

1. Render <Pressable accessibilityRole="switch" accessibilityState={{ checked: true }} accessibilityLabel="Notifications" />.
2. Turn on TalkBack and focus the element.
3. Hear "checked. on." in the announcement.

Expected

The state is read once ("on"), not twice.

Suggested fix

In ReactAccessibilityDelegate, when accessibilityState.checked is set, also call ViewCompat.setStateDescription (or AccessibilityNodeInfoCompat.setStateDescription). For role switch it would be "on"/"off", and for role checkbox "checked"/"not checked", using Android's own localized strings. Alternatively, expose accessibilityValue.text as the stateDescription.

Versions

• React Native 0.85.3 (Expo SDK 56). Also confirmed on main up to v0.88.0-rc.1 by reading the source.
• TalkBack 17.

从 ReactAccessibilityDelegate.kt 中 STATE_CHECKED 的处理开始，跟踪 accessibilityRole 和 accessibilityState 如何传递到 Android 节点。比较针对 switch 和 checkbox 角色的 ViewCompat 或 AccessibilityNodeInfoCompat stateDescription 建议行为，然后验证公告不再重复状态，同时现有的无障碍行为保持不变。