### 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.
ERR_FAIL_COND_V(instance == XR_NULL_HANDLE, RID());
	Action action;
	action.name = p_name;
	ActionSet *action_set = action_set_owner.get_or_null(p_action_set);
	ERR_FAIL_NULL_V(action_set, RID());
	ERR_FAIL_COND_V(action_set->handle == XR_NULL_HANDLE, RID());
	action.action_set_rid = p_action_set;
	switch (p_action_type) {
		case OpenXRAction::OPENXR_ACTION_BOOL:
			action.action_type = XR_ACTION_TYPE_BOOLEAN_INPUT;
			break;
		case OpenXRAction::OPENXR_ACTION_FLOAT:
			action.action_type = XR_ACTION_TYPE_FLOAT_INPUT;
			break;
		case OpenXRAction::OPENXR_ACTION_VECTOR2:
			action.action_type = XR_ACTION_TYPE_VECTOR2F_INPUT;
			break;
		case OpenXRAction::OPENXR_ACTION_POSE:
			action.action_type = XR_ACTION_TYPE_POSE_INPUT;
			break;
		case OpenXRAction::OPENXR_ACTION_HAPTIC:
			action.action_type = XR_ACTION_TYPE_VIBRATION_OUTPUT;
			break;
		default:
			ERR_FAIL_V(RID());
			break;
	}
	Vector<XrPath> toplevel_paths;
	for (int i = 0; i < p_trackers.size(); i++) {