### 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.
destroy_session();
	destroy_instance();
}
void OpenXRAPI::set_xr_interface(OpenXRInterface *p_xr_interface) {
	xr_interface = p_xr_interface;
}
void OpenXRAPI::register_extension_wrapper(OpenXRExtensionWrapper *p_extension_wrapper) {
	registered_extension_wrappers.push_back(p_extension_wrapper);
}
void OpenXRAPI::unregister_extension_wrapper(OpenXRExtensionWrapper *p_extension_wrapper) {
	registered_extension_wrappers.erase(p_extension_wrapper);
}
void OpenXRAPI::register_extension_metadata() {
	for (OpenXRExtensionWrapper *extension_wrapper : registered_extension_wrappers) {
		extension_wrapper->on_register_metadata();
	}
}
void OpenXRAPI::cleanup_extension_wrappers() {