============================================================================ COMPUTED ASYNC (DERIVED ASYNC SIGNALS)

Computed signal that handles async operations.

ComputedAsync automatically recomputes when dependencies change and manages loading/error states.

Example:

class UserController extends NeuronController {
  late final userId = Signal<int>(1).bind(this);

  late final user = ComputedAsync<User>(
    () => api.getUser(userId.val),
    [userId],
  ).bind(this);
}

// In UI
AsyncSlot<User>(
  connect: controller.user,
  onData: (ctx, user) => Text(user.name),
)