refactor: remove double sprites

packages/pinball_components/lib/src/components/plunger.dart

@@ -31,8 +31,6 @@ class Plunger extends BodyComponent with InitialPosition, Layered, ZIndex {
   /// Distance the plunger can lower.
   final double compressionDistance;
 
-  late final _PlungerSpriteAnimationGroupComponent _spriteComponent;
-
   List<FixtureDef> _createFixtureDefs() {
     final fixturesDef = <FixtureDef>[];
 
@@ -88,8 +86,10 @@ class Plunger extends BodyComponent with InitialPosition, Layered, ZIndex {
 
   /// Set a constant downward velocity on the [Plunger].
   void pull() {
+    final sprite = firstChild<_PlungerSpriteAnimationGroupComponent>()!;
+
     body.linearVelocity = Vector2(0, 7);
-    _spriteComponent.pull();
+    sprite.pull();
   }
 
   /// Set an upward velocity on the [Plunger].
@@ -97,10 +97,12 @@ class Plunger extends BodyComponent with InitialPosition, Layered, ZIndex {
   /// The velocity's magnitude depends on how far the [Plunger] has been pulled
   /// from its original [initialPosition].
   void release() {
+    final sprite = firstChild<_PlungerSpriteAnimationGroupComponent>()!;
+
     _pullingDownTime = 0;
     final velocity = (initialPosition.y - body.position.y) * 11;
     body.linearVelocity = Vector2(0, velocity);
-    _spriteComponent.release();
+    sprite.release();
   }
 
   @override
@@ -137,9 +139,6 @@ class Plunger extends BodyComponent with InitialPosition, Layered, ZIndex {
   Future<void> onLoad() async {
     await super.onLoad();
     await _anchorToJoint();
-
-    _spriteComponent = _PlungerSpriteAnimationGroupComponent();
-    await add(_spriteComponent);
   }
 }