feat: Add DoubleTapCallbacks that receives double-tap events. (#2327)

As-is
As mentioned in #2321, the user needs to propagate double-tap events to the component tree using DoubleTapDetector & propagateToChildren until now.

To-be
Any components that are mixed into the DoubleTapCallbacks receive double-tap-related events.
Same as DragCallbacks, there is no need to add mixin to the game like HasDoubleTapCallbaks as before.

examples/lib/stories/input/double_tap_callbacks_example.dart

@@ -0,0 +1,65 @@
+import 'package:examples/commons/ember.dart';
+import 'package:flame/components.dart';
+import 'package:flame/experimental.dart';
+import 'package:flame/game.dart';
+import 'package:flutter/material.dart';
+
+class DoubleTapCallbacksExample extends FlameGame with DoubleTapCallbacks {
+  static const String description = '''
+  In this example, we show how you can use the `DoubleTapCallbacks` mixin on
+  a `Component`. Double tap Ember and see her color changing.
+  The example also adds white circles when double-tapping on the game area.
+''';
+
+  @override
+  Future<void> onLoad() async {
+    children.register<DoubleTappableEmber>();
+  }
+
+  @override
+  void onGameResize(Vector2 canvasSize) {
+    children
+        .query<DoubleTappableEmber>()
+        .forEach((element) => element.removeFromParent());
+    add(DoubleTappableEmber(position: canvasSize / 2));
+
+    super.onGameResize(canvasSize);
+  }
+
+  @override
+  void onDoubleTapDown(DoubleTapDownEvent event) {
+    add(
+      CircleComponent(
+        radius: 30,
+        position: event.localPosition,
+        anchor: Anchor.center,
+      ),
+    );
+  }
+}
+
+class DoubleTappableEmber extends Ember with DoubleTapCallbacks {
+  @override
+  bool debugMode = true;
+
+  DoubleTappableEmber({Vector2? position})
+      : super(
+          position: position ?? Vector2.all(100),
+          size: Vector2.all(100),
+        );
+
+  @override
+  void onDoubleTapUp(DoubleTapEvent event) {
+    debugColor = Colors.greenAccent;
+  }
+
+  @override
+  void onDoubleTapCancel(DoubleTapCancelEvent event) {
+    debugColor = Colors.red;
+  }
+
+  @override
+  void onDoubleTapDown(DoubleTapDownEvent event) {
+    debugColor = Colors.blue;
+  }
+}