Storage: branding access (#52412)
Storage: branding access (#52412)

* Storage: add special users for system branding access

* Storage: explicit global org id

* Storage: initialize org storages with global org id

* Storage: add comments

* Storage: simplify - use orgId: 1 for systembranding
grafana/grafana,grafana/grafana,grafana/grafana,grafana/grafana,grafana/grafana,grafana/grafana,grafana/grafana