bug: vue, memoryRouter + tapping tab while inside nested route does nothing

### Prerequisites

- [X] I have read the [Contributing Guidelines](https://github.com/ionic-team/ionic-framework/blob/main/docs/CONTRIBUTING.md#creating-an-issue).
- [X] I agree to follow the [Code of Conduct](https://ionicframework.com/code-of-conduct).
- [X] I have searched for [existing issues](https://github.com/ionic-team/ionic-framework/issues) that already report this problem, without success.

### Ionic Framework Version

v8.x

### Current Behavior

When using memory history router and tapping on ion-tab while being on a nested route, nothing happens.
While debugging I found that `route.position` is `undefined` when trying to reset to root page. That maybe expected, not sure.

When using web history router, navigation to root page works as expected. I have to use memory router to make swipe back working inside PWA.

### Expected Behavior

Navigate back to the root page of the tab.

### Steps to Reproduce

1. Clone (ionic-vue-conference-app)[https://github.com/ionic-team/ionic-vue-conference-app]
2. Use memory router in router.ts (`createMemoryHistory`)
3. Click on any session on sessions tab
4. Click on schedule tab in the tab bar
5. Nothing happens

### Code Reproduction URL

https://github.com/ionic-team/ionic-vue-conference-app

### Ionic Info

```
[ERROR] Invalid project type: vue-vite (project config: ./ionic.config.json).

Project type must be one of: angular, ionic-angular, ionic1, custom, react, vue

Bad project type: undefined
```

### Additional Information

_No response_

在 ionic-vue-conference-app 中使用 router.ts 里的 createMemoryHistory 重现该问题：从 sessions 标签页打开一个会话，然后点击 schedule 标签页。检查标签页导航，以及读取 route.position 的根页面重置路径。完成标准是：从嵌套路由点击另一个标签页时，会导航回该标签页的根页面。

由索引模型根据 Issue 内容生成。