### 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.
xrDestroySwapchain(new_swapchain);
		return false;
	}
	r_swapchain = new_swapchain;
	return true;
}
bool OpenXRAPI::on_state_idle() {
	print_verbose("On state idle");
	for (OpenXRExtensionWrapper *wrapper : registered_extension_wrappers) {
		wrapper->on_state_idle();
	}
	return true;
}
bool OpenXRAPI::on_state_ready() {
	print_verbose("On state ready");
	
	XrSessionBeginInfo session_begin_info = {
		XR_TYPE_SESSION_BEGIN_INFO, 
		nullptr, 
		view_configuration 
	};
	XrResult result = xrBeginSession(session, &session_begin_info);
	if (XR_FAILED(result)) {
		print_line("OpenXR: Failed to begin session [", get_error_string(result), "]");
		return false;
	}