### 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.
frame_state.predictedDisplayTime, 
			environment_blend_mode, 
			0, 
			nullptr 
		};
		result = xrEndFrame(session, &frame_end_info);
		if (XR_FAILED(result)) {
			print_line("OpenXR: failed to end frame! [", get_error_string(result), "]");
			return;
		}
		
		return;
	}
	
	for (int i = 0; i < OPENXR_SWAPCHAIN_MAX; i++) {
		if (swapchains[i].image_acquired) {
			swapchains[i].image_acquired = false; 
			release_image(swapchains[i]);
		}
	}
	for (uint32_t eye = 0; eye < view_count; eye++) {
		projection_views[eye].fov = views[eye].fov;
		projection_views[eye].pose = views[eye].pose;
	}
	Vector<const XrCompositionLayerBaseHeader *> layers_list;
	
	for (OpenXRCompositionLayerProvider *provider : composition_layer_providers) {
		XrCompositionLayerBaseHeader *layer = provider->get_composition_layer();
		if (layer) {
			layers_list.push_back(layer);