### 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.
return false;
}
XRInterface::PlayAreaMode OpenXRInterface::get_play_area_mode() const {
	return XRInterface::XR_PLAY_AREA_UNKNOWN;
}
bool OpenXRInterface::set_play_area_mode(XRInterface::PlayAreaMode p_mode) {
	return false;
}
float OpenXRInterface::get_display_refresh_rate() const {
	if (openxr_api == nullptr) {
		return 0.0;
	} else if (!openxr_api->is_initialized()) {
		return 0.0;
	} else {
		return openxr_api->get_display_refresh_rate();
	}
}
void OpenXRInterface::set_display_refresh_rate(float p_refresh_rate) {
	if (openxr_api == nullptr) {
		return;
	} else if (!openxr_api->is_initialized()) {
		return;
	} else {
		openxr_api->set_display_refresh_rate(p_refresh_rate);
	}
}
Array OpenXRInterface::get_available_display_refresh_rates() const {