docs: Fix naming of drag- and tap-callbacks examples (#2873)

Fix naming of drag- and tap-callbacks examples

examples/lib/stories/input/drag_callbacks_example.dart

@@ -0,0 +1,45 @@
+import 'package:examples/commons/ember.dart';
+import 'package:flame/events.dart';
+import 'package:flame/game.dart';
+import 'package:flutter/material.dart' show Colors;
+
+class DragCallbacksExample extends FlameGame {
+  static const String description = '''
+    In this example we show you can use the `DragCallbacks` mixin on
+    `PositionComponent`s. Drag around the Embers and see their position
+    changing.
+  ''';
+
+  DragCallbacksExample({required this.zoom});
+
+  final double zoom;
+  late final DraggableEmber square;
+
+  @override
+  Future<void> onLoad() async {
+    camera.viewfinder.zoom = zoom;
+    world.add(square = DraggableEmber());
+    world.add(DraggableEmber()..y = 350);
+  }
+}
+
+// Note: this component does not consider the possibility of multiple
+// simultaneous drags with different pointerIds.
+class DraggableEmber extends Ember with DragCallbacks {
+  @override
+  bool debugMode = true;
+
+  DraggableEmber({super.position}) : super(size: Vector2.all(100));
+
+  @override
+  void update(double dt) {
+    super.update(dt);
+    debugColor = isDragged ? Colors.greenAccent : Colors.purple;
+  }
+
+  @override
+  void onDragUpdate(DragUpdateEvent event) {
+    event.continuePropagation = true;
+    return;
+  }
+}