Alerting: Add support for alpha rules apis in legacy storage

Rules created in the new api makes the rule have no group in the database, but the rule is returned in the old group api with a sentinel group name formatted with the rule uid for compatiblity with the old api.
This makes the UI continue to work with the rules without a group, and the ruler will continue to work with the rules without a group.

Rules are not allowed to be created in the provisioning api with a NoGroup sentinel mask, but NoGroup rules can be manipulated through both the new and old apis.

Co-authored-by: William Wernert <william.wernert@grafana.com>

go.mod

@@ -235,6 +235,7 @@ require (
 	github.com/grafana/grafana/apps/advisor v0.0.0 // @grafana/plugins-platform-backend
 	github.com/grafana/grafana/apps/alerting/alertenrichment v0.0.0 // @grafana/alerting-backend
 	github.com/grafana/grafana/apps/alerting/notifications v0.0.0 // @grafana/alerting-backend
+	github.com/grafana/grafana/apps/alerting/rules v0.0.0 // @grafana/alerting-backend
 	github.com/grafana/grafana/apps/dashboard v0.0.0 // @grafana/grafana-app-platform-squad @grafana/dashboards-squad
 	github.com/grafana/grafana/apps/folder v0.0.0 // @grafana/grafana-search-and-storage
 	github.com/grafana/grafana/apps/iam v0.0.0 // @grafana/identity-access-team
@@ -261,6 +262,7 @@ replace (
 	github.com/grafana/grafana/apps/advisor => ./apps/advisor
 	github.com/grafana/grafana/apps/alerting/alertenrichment => ./apps/alerting/alertenrichment
 	github.com/grafana/grafana/apps/alerting/notifications => ./apps/alerting/notifications
+	github.com/grafana/grafana/apps/alerting/rules => ./apps/alerting/rules
 	github.com/grafana/grafana/apps/dashboard => ./apps/dashboard
 	github.com/grafana/grafana/apps/folder => ./apps/folder
 	github.com/grafana/grafana/apps/iam => ./apps/iam