feat: Separator component

### 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

A dedicated component to spontaneously create a separator, horizontal or vertical depending of usages. Something similar to items separator, but without needs to be in items group or something to make it, and a vertical variant.

### Describe the Use Case

Allows to split several parts of an app smoothly, without having to write a custom css

### Describe Preferred Solution

Ideally something really light, with just a `vertical` bool to switch to a vertical mod, and just an empty styled div I guess ? Taking children doesn't seems to be logic

### Describe Alternatives

Except a custom styled component, not really possible right now

### Related Code

_No response_

### Additional Information

Using an empty item needs to make some tricks to remove it's default height, that is verbose for a simple thing like that