feat: ion-datetime to show day picker when selecting month and year

### 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 include this feature request, without success.

### Describe the Feature Request

Can we have day picker when selecting month and year ?


### Describe the Use Case

A day picker when selecting month and date would be a better UX.

### Describe Preferred Solution

currently this i my setup:

html:
```
@if(!isDateTIme){

}
@else{

}
```

.ts:

```
submitDob(e: any) {
this.isDateTIme = false;
}

onDateFocus(e: any) {
this.isDateTIme = true;
}
```

### Describe Alternatives

none

### Related Code

```
@if(!isDateTIme){

}
@else{

}
```

```
submitDob(e: any) {
this.isDateTIme = false;
}

onDateFocus(e: any) {
this.isDateTIme = true;
}
```

### Additional Information

_No response_

No source files, tests, or entry points are named. Start by reproducing the provided ion-datetime Angular setup with month and year selection, then inspect the component implementation and existing date-picker tests; done means the agreed UX for showing a day picker is implemented and covered by tests.

由索引模型根据 Issue 内容生成。