### 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.
XRServer *xr_server = XRServer::get_singleton();
	ERR_FAIL_NULL(xr_server);
	ERR_FAIL_NULL(openxr_api);
	for (int i = 0; i < trackers.size(); i++) {
		Tracker *tracker = trackers[i];
		openxr_api->tracker_free(tracker->tracker_rid);
		xr_server->remove_tracker(tracker->positional_tracker);
		tracker->positional_tracker.unref();
		memdelete(tracker);
	}
	trackers.clear();
}
void OpenXRInterface::free_interaction_profiles() {
	ERR_FAIL_NULL(openxr_api);
	for (int i = 0; i < interaction_profiles.size(); i++) {
		openxr_api->interaction_profile_free(interaction_profiles[i]);
	}
	interaction_profiles.clear();
}
bool OpenXRInterface::initialize_on_startup() const {
	if (openxr_api == nullptr) {
		return false;
	} else if (!openxr_api->is_initialized()) {
		return false;
	} else {
		return true;
	}
}
bool OpenXRInterface::is_initialized() const {