Adds infrastructure/networking/traefik-helmchartconfig.yaml so the k3s
Traefik overrides (badger plugin, allowCrossNamespace, letsencrypt
resolver + persistent acme.json, non-root fsGroup) are tracked in git.
kube-system is not managed by ArgoCD in this cluster; kubectl apply of
this file is the manual reproducibility path.
Refs: DEV-455, DEV-457
Co-Authored-By: Paperclip <noreply@paperclip.ing>