How to prevent overscrolling of screen even if there's a not so much of elements in viewport?

[Nurik7]

I've made small explanation of what I have and what I'm expecting

https://github.com/kspo/super_cupertino_navigation_bar/assets/20270296/2e949c35-95c9-4b00-855d-bd5bc4d26eb7

here's the code of actual Example Widget:

class Example extends StatelessWidget {
  const Example({Key? key}) : super(key: key);

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: CustomScrollView(
        slivers: [
          CupertinoSliverNavigationBar(
            largeTitle: Text("Example screen"),
          ),
          SliverList.builder(
            itemBuilder: (context, index) {
              return Container(
                padding: const EdgeInsets.symmetric(vertical: 10, horizontal: 10),
                child: const Row(
                  crossAxisAlignment: CrossAxisAlignment.start,
                  children: [
                    Icon(
                      CupertinoIcons.check_mark_circled,
                      color: CupertinoColors.systemIndigo,
                    ),
                    SizedBox(
                      width: 15,
                    ),
                    Expanded(
                      child: Column(
                        mainAxisAlignment: MainAxisAlignment.start,
                        crossAxisAlignment: CrossAxisAlignment.start,
                        children: [
                          Opacity(opacity: 0.5, child: Text("kspo/super_cupertino_navigation_bar")),
                          SizedBox(
                            height: 5,
                          ),
                          Text("Placeholder text offset when scaling up system accessibility text size"),
                          SizedBox(
                            height: 5,
                          ),
                          Opacity(
                            opacity: 0.5,
                            child: Text(
                              "@kspo, actually, if you have no urgency with your project,",
                              maxLines: 1,
                              overflow: TextOverflow.ellipsis,
                            ),
                          ),
                        ],
                      ),
                    )
                  ],
                ),
              );
            },
            itemCount: 1,
          ),
        ],
      ),
    );
  }
}