Extend the UrlSuffixTransformer to process the node's compound children nodes

The processing is still in `portal-server-lib`
https://github.com/openmfp/portal-server-lib/blob/f405ea54cc8b4f05dd0754c55a626f44cf6ee0d8/src/config/luigi/luigi-data/content-configuration-luigi-data.service.ts#L150

and should be here along with the nodes `urlSuffix` processing