### 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.
print_line("OpenXR: Couldn't locate views [", get_error_string(result), "]");
		return;
	}
	bool pose_valid = true;
	for (uint64_t i = 0; i < view_count_output; i++) {
		if ((view_state.viewStateFlags & XR_VIEW_STATE_ORIENTATION_VALID_BIT) == 0 ||
				(view_state.viewStateFlags & XR_VIEW_STATE_POSITION_VALID_BIT) == 0) {
			pose_valid = false;
		}
	}
	if (view_pose_valid != pose_valid) {
		view_pose_valid = pose_valid;
		if (!view_pose_valid) {
			print_verbose("OpenXR View pose became invalid");
		} else {
			print_verbose("OpenXR View pose became valid");
		}
	}
	
	XrFrameBeginInfo frame_begin_info = {
		XR_TYPE_FRAME_BEGIN_INFO, 
		nullptr 
	};
	result = xrBeginFrame(session, &frame_begin_info);
	if (XR_FAILED(result)) {
		print_line("OpenXR: failed to being frame [", get_error_string(result), "]");
		return;
	}
}
bool OpenXRAPI::pre_draw_viewport(RID p_render_target) {