### 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 false;
	} else {
		return openxr_api->is_foveation_supported();
	}
}
int OpenXRInterface::get_foveation_level() const {
	if (openxr_api == nullptr) {
		return 0;
	} else {
		return openxr_api->get_foveation_level();
	}
}
void OpenXRInterface::set_foveation_level(int p_foveation_level) {
	if (openxr_api == nullptr) {
		return;
	} else {
		openxr_api->set_foveation_level(p_foveation_level);
	}
}
bool OpenXRInterface::get_foveation_dynamic() const {
	if (openxr_api == nullptr) {
		return false;
	} else {
		return openxr_api->get_foveation_dynamic();
	}
}
void OpenXRInterface::set_foveation_dynamic(bool p_foveation_dynamic) {