feat(verifier): scope random-action targets to app package

Random tap/doubleTap/type/swipe candidates now exclude nodes whose package differs from the app under test, so exploration never fuzzes the soft keyboard, system UI, or permission dialogs. An unset app package or an element with no package stays in scope, preserving behavior on iOS.

internal/verifier/worker.go

@@ -39,6 +39,8 @@ type Verifier struct {
 	stepTime       time.Time
 	runStart       time.Time
 
+	appPackage string
+
 	rng *rand.Rand
 }
 
@@ -48,6 +50,14 @@ func WithRand(rng *rand.Rand) Option {
 	return func(v *Verifier) { v.rng = rng }
 }
 
+// WithAppPackage scopes random-action target selection to the app under test.
+// Nodes belonging to another package (the soft keyboard, system UI, permission
+// dialogs) are excluded so exploration never spends steps fuzzing the IME or
+// inserting keyboard glyphs into fields. Empty package keeps current behavior.
+func WithAppPackage(appPackage string) Option {
+	return func(v *Verifier) { v.appPackage = appPackage }
+}
+
 func New(options ...Option) (*Verifier, error) {
 	verifier := &Verifier{
 		runtime:       goja.New(),
@@ -565,6 +575,17 @@ func (v *Verifier) generateRandomDoubleTap() (Action, error) {
 	return v.generateRandomTapKind(ActionKindDoubleTap)
 }
 
+// inScope reports whether an element belongs to the app under test. Nodes from
+// another package (the soft keyboard, system UI, permission dialogs) are out of
+// scope. An unset app package or an element with no package falls through to in
+// scope, preserving behavior on platforms that omit the attribute (e.g. iOS).
+func (v *Verifier) inScope(element *hierarchy.Element) bool {
+	if v.appPackage == "" || element.Package == "" {
+		return true
+	}
+	return element.Package == v.appPackage
+}
+
 func (v *Verifier) generateRandomTapKind(kind ActionKind) (Action, error) {
 	if v.lastTree == nil {
 		return Action{}, ErrNoAction
@@ -574,6 +595,9 @@ func (v *Verifier) generateRandomTapKind(kind ActionKind) (Action, error) {
 		if !element.Clickable || !element.Enabled {
 			continue
 		}
+		if !v.inScope(element) {
+			continue
+		}
 		if element.Bounds.Right-element.Bounds.Left <= 0 || element.Bounds.Bottom-element.Bounds.Top <= 0 {
 			continue
 		}
@@ -621,6 +645,9 @@ func (v *Verifier) generateRandomInput() (Action, error) {
 		if !element.Editable || !element.Enabled {
 			continue
 		}
+		if !v.inScope(element) {
+			continue
+		}
 		if element.Bounds.Right-element.Bounds.Left <= 0 || element.Bounds.Bottom-element.Bounds.Top <= 0 {
 			continue
 		}
@@ -642,7 +669,16 @@ func (v *Verifier) generateRandomSwipe() (Action, error) {
 	if v.lastTree == nil || len(v.lastTree.Elements) == 0 {
 		return Action{}, ErrNoAction
 	}
-	element := v.lastTree.Elements[v.rng.IntN(len(v.lastTree.Elements))]
+	candidates := make([]*hierarchy.Element, 0, len(v.lastTree.Elements))
+	for _, element := range v.lastTree.Elements {
+		if v.inScope(element) {
+			candidates = append(candidates, element)
+		}
+	}
+	if len(candidates) == 0 {
+		return Action{}, ErrNoAction
+	}
+	element := candidates[v.rng.IntN(len(candidates))]
 	cx, cy := element.Bounds.Center()
 	if cx <= 0 || cy <= 0 {
 		return Action{}, ErrNoAction