Most of this folder comes from Vegasbrianc's Prometheus stack.
To log in Grafana, the same Keycloak client as for the Node-REDs is used. You can log in as production-owner for admin access. developper has by default the Editor role within Grafana, like any user with the developper role.
There is a single dashboard available which is preloaded. It will show you usage of all containers connected to traefik and from the host.
For receiving or configuring alerts, kindly review Prometheus documentation and Alertmanager's.