### Godot version

4.2.dev 80de898d721f952dac0b102d48bb73d6b02ee1e8

### System information

OpenXR

### Issue description

The Godot 3 OpenXR plugin supported obtaining boundary/guardian information in order to obtain play space logic. While we do have a function in the `XRInterface` in Godot 4 that is supposed to retrieve this information (`get_play_area`) it is not implemented on the Godot 4 `OpenXRInterface`.

This logic needs to be ported.

### Steps to reproduce

Call `get_play_area`, be amazed by it not returning data :P

### Minimal reproduction project

Any XR project.
if (openxr_api == nullptr) {
		return;
	} else {
		openxr_api->set_foveation_dynamic(p_foveation_dynamic);
	}
}
Size2 OpenXRInterface::get_render_target_size() {
	if (openxr_api == nullptr) {
		return Size2();
	} else {
		return openxr_api->get_recommended_target_size();
	}
}
uint32_t OpenXRInterface::get_view_count() {
	
	return 2;
}
void OpenXRInterface::_set_default_pos(Transform3D &p_transform, double p_world_scale, uint64_t p_eye) {
	p_transform = Transform3D();
	
	p_transform.origin.y = 1.5 * p_world_scale;
	
	if (p_eye == 1) {
		p_transform.origin.x = 0.03 * p_world_scale;
	} else if (p_eye == 2) {
		p_transform.origin.x = -0.03 * p_world_scale;
	}
}
Transform3D OpenXRInterface::get_camera_transform() {