### 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 XRInterface::XR_VR + XRInterface::XR_STEREO;
};
PackedStringArray OpenXRInterface::get_suggested_tracker_names() const {
	
	PackedStringArray arr = {
		"left_hand", 
		"right_hand", 
		"/user/treadmill",
		
		
		
		"/user/vive_tracker_htcx/role/handheld_object",
		"/user/vive_tracker_htcx/role/left_foot",
		"/user/vive_tracker_htcx/role/right_foot",
		"/user/vive_tracker_htcx/role/left_shoulder",
		"/user/vive_tracker_htcx/role/right_shoulder",
		"/user/vive_tracker_htcx/role/left_elbow",
		"/user/vive_tracker_htcx/role/right_elbow",
		"/user/vive_tracker_htcx/role/left_knee",
		"/user/vive_tracker_htcx/role/right_knee",
		"/user/vive_tracker_htcx/role/waist",
		"/user/vive_tracker_htcx/role/chest",
		"/user/vive_tracker_htcx/role/camera",
		"/user/vive_tracker_htcx/role/keyboard",
		"/user/eyes_ext",
	};
	return arr;
}
XRInterface::TrackingStatus OpenXRInterface::get_tracking_status() const {