### 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.
#ifndef OPENXR_API_H
#define OPENXR_API_H
#include "action_map/openxr_action.h"
#include "extensions/openxr_composition_layer_provider.h"
#include "extensions/openxr_extension_wrapper.h"
#include "util.h"
#include "core/error/error_macros.h"
#include "core/math/projection.h"
#include "core/math/transform_3d.h"
#include "core/math/vector2.h"
#include "core/os/memory.h"
#include "core/string/print_string.h"
#include "core/string/ustring.h"
#include "core/templates/rb_map.h"
#include "core/templates/rid_owner.h"
#include "core/templates/vector.h"
#include "servers/xr/xr_pose.h"
#include <openxr/openxr.h>
class OpenXRInterface;