### 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_verbose("On state existing");
	for (OpenXRExtensionWrapper *wrapper : registered_extension_wrappers) {
		wrapper->on_state_exiting();
	}
	
	return true;
}
void OpenXRAPI::set_form_factor(XrFormFactor p_form_factor) {
	ERR_FAIL_COND(is_initialized());
	form_factor = p_form_factor;
}
void OpenXRAPI::set_view_configuration(XrViewConfigurationType p_view_configuration) {
	ERR_FAIL_COND(is_initialized());
	view_configuration = p_view_configuration;
}
void OpenXRAPI::set_reference_space(XrReferenceSpaceType p_reference_space) {
	ERR_FAIL_COND(is_initialized());
	reference_space = p_reference_space;
}
void OpenXRAPI::set_submit_depth_buffer(bool p_submit_depth_buffer) {
	ERR_FAIL_COND(is_initialized());
	submit_depth_buffer = p_submit_depth_buffer;
}
bool OpenXRAPI::is_initialized() {