Hide SwipeActionsView from the accessibility tree (#616)

When a list item has swipe actions, the `DefaultSwipeActionButton`
instances stayed in the accessibility tree even while the swipe was
closed — the buttons were positioned off-screen, so VoiceOver ignores
them under standard conditions but animations like rotation could still
expose them momentarily allowing selection of "Void"/"Repeat"/"Delete"
elements.

`SwipeActionsView` now starts with `accessibilityElementsHidden = true`
(matching its initial `.closed` state) and toggles in `apply(state:)`:
hidden while `.closed`, exposed once the actions are open/swiping. The
row's `accessibilityCustomActions` is unaffected, so VoiceOver can still
trigger swipe actions via the Actions rotor without opening the swipe;
once opened, the visible buttons are also reachable directly.

### Checklist

Please do the following before merging:

- [ ] Ensure any public-facing changes are reflected in the
[changelog](https://github.com/square/Listable/blob/main/CHANGELOG.md).
Include them in the `Main` section.

---------

Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: RoyalPineapple

CHANGELOG.md

@@ -2,6 +2,8 @@
 
 ### Fixed
 
+- Hid swipe action buttons from VoiceOver while the swipe is closed. The buttons become accessibility elements again once the swipe is open, so the row's `accessibilityCustomActions` no longer competes with invisible, off-screen buttons.
+
 ### Added
 
 ### Removed

ListableUI/Sources/Internal/SwipeActionsView.swift

@@ -67,6 +67,7 @@ final class SwipeActionsView: UIView {
         self.didPerformAction = didPerformAction
         super.init(frame: .zero)
         clipsToBounds = true
+        accessibilityElementsHidden = true
 
         addSubview(container)
     }
@@ -226,7 +227,9 @@ final class SwipeActionsView: UIView {
     func apply(state newState: SwipeActionState) {
         let priorState = state
         state = newState
-        
+
+        accessibilityElementsHidden = (newState == .closed)
+
         guard newState.isRelevantFor(side: side) else {
             return
         }