The platform-engineer ArgoCD account was created (argocd-cm.yaml) with
apiKey capability, but no argocd-rbac-cm ConfigMap existed, so the account
had default (empty) RBAC and every API call returned 403.
This adds the RBAC policy granting the platform-engineer role:
- get applications (all projects/namespaces)
- sync applications (all projects/namespaces)
- get projects
Needed for the platform-engineer cron jobs to read app health and trigger
syncs via the ArgoCD API.
