useComputed top-level property

Creates a computed value hook that derives from reactive dependencies.

The computed value is cached and only recalculates when its dependencies change.

Parameters:

• getter: Function that computes the derived value
• onDebug: Optional debug callback for reactive system debugging

Returns: A Computed that automatically updates when dependencies change

Example:

setup(context, props) {
  final count = useSignal(5);
  final doubled = useComputed(() => count.value * 2);
  final message = useComputed(() => 'Count is ${count.value}');

  return () => Text('${message.value}, doubled: ${doubled.value}');
}