Alerting: Support recording rule struct in provisioning API (#87849)

* Support record struct in provisioning API

* Update api spec

* Use record field

* Restrict API endpoints following toggle

* Fix swagger spec

* Add recording rule validation to store validator

pkg/services/ngalert/api/api.go

@@ -164,6 +164,8 @@ func (api *API) RegisterAPIEndpoints(m *metrics.API) {
 		templates:           api.Templates,
 		muteTimings:         api.MuteTimings,
 		alertRules:          api.AlertRules,
+		// XXX: Used to flag recording rules, remove when FT is removed
+		featureManager: api.FeatureManager,
 	}), m)
 
 	api.RegisterHistoryApiEndpoints(NewStateHistoryApi(&HistorySrv{