fix: getDescendants isEmpty removeLast error

app/src/main/java/li/songe/gkd/service/AbExt.kt

@@ -149,6 +149,7 @@ val abTransform = Transform(
     getDescendants = { node ->
         sequence {
             val stack = getChildren(node).toMutableList()
+            if (stack.isEmpty()) return@sequence
             val tempNodes = mutableListOf<AccessibilityNodeInfo>()
             do {
                 val top = stack.removeLast()

selector/src/commonMain/kotlin/li/songe/selector/Transform.kt

@@ -53,6 +53,7 @@ class Transform<T>(
         sequence { //            深度优先 先序遍历
             //            https://developer.mozilla.org/zh-CN/docs/Web/API/Document/querySelector
             val stack = getChildren(node).toMutableList()
+            if (stack.isEmpty()) return@sequence
             stack.reverse()
             val tempNodes = mutableListOf<T>()
             do {