Alerting: Feature toggle to disallow sending alerts externally (#87982)

* Define feature toggle

* Implement feature toggle

pkg/services/featuremgmt/registry.go

@@ -1282,6 +1282,15 @@ var (
 			Owner:        identityAccessTeam,
 			HideFromDocs: true,
 		},
+		{
+			Name:              "alertingDisableSendAlertsExternal",
+			Description:       "Disables the ability to send alerts to an external Alertmanager datasource.",
+			Stage:             FeatureStageExperimental,
+			Owner:             grafanaAlertingSquad,
+			AllowSelfServe:    false,
+			HideFromDocs:      true,
+			HideFromAdminPage: true,
+		},
 	}
 )
 

pkg/services/featuremgmt/toggles_gen.csv

@@ -171,3 +171,4 @@ newDashboardSharingComponent,experimental,@grafana/sharing-squad,false,false,tru
 notificationBanner,experimental,@grafana/grafana-frontend-platform,false,false,false
 dashboardRestore,experimental,@grafana/grafana-frontend-platform,false,false,false
 datasourceProxyDisableRBAC,GA,@grafana/identity-access-team,false,false,false
+alertingDisableSendAlertsExternal,experimental,@grafana/alerting-squad,false,false,false

pkg/services/featuremgmt/toggles_gen.go

@@ -694,4 +694,8 @@ const (
 	// FlagDatasourceProxyDisableRBAC
 	// Disables applying a plugin route's ReqAction field to authorization
 	FlagDatasourceProxyDisableRBAC = "datasourceProxyDisableRBAC"
+
+	// FlagAlertingDisableSendAlertsExternal
+	// Disables the ability to send alerts to an external Alertmanager datasource.
+	FlagAlertingDisableSendAlertsExternal = "alertingDisableSendAlertsExternal"
 )