fix: prevent swipe back gesture during push/pop transitions (#609)

This fix resolves a race condition where swiping back during a push
transition caused the app to freeze. The issue was particularly severe
when using historySyncPlugin, causing complete UI lockup.

The root cause was that the swipe gesture listener on the edge element
did not check if the activity was in an active transition state before
starting the swipe. This allowed users to initiate a swipe gesture
while a new activity was sliding in (enter-active) or sliding out
(exit-active), creating conflicting animations.

Changes:
- Added transition state check in useStyleEffectSwipeBack's onTouchStart
- Swipe gestures are now blocked when activity is in "enter-active" or
  "exit-active" transition states
- Only allows swipe to start when activity is in stable state
  ("enter-done" or "exit-done")

Fixes #609

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <[email protected]>

Author: claude

extensions/react-ui-core/src/useStyleEffectSwipeBack.ts

@@ -208,6 +208,12 @@ export function useStyleEffectSwipeBack({
       }
 
       const onTouchStart = (e: TouchEvent) => {
+        // Prevent swipe gesture from starting during push/pop transitions
+        const transitionState = getActivityTransitionState();
+        if (transitionState === "enter-active" || transitionState === "exit-active") {
+          return;
+        }
+
         const { activeElement } = document as any;
 
         activeElement?.blur?.();