[MM-25089] Migrate server busy endpoints to local mode (#14883)

api4/system_local.go

@@ -5,4 +5,7 @@ package api4
 
 func (api *API) InitSystemLocal() {
 	api.BaseRoutes.ApiRoot.Handle("/logs", api.ApiLocal(getLogs)).Methods("GET")
+	api.BaseRoutes.ApiRoot.Handle("/server_busy", api.ApiLocal(setServerBusy)).Methods("POST")
+	api.BaseRoutes.ApiRoot.Handle("/server_busy", api.ApiLocal(getServerBusyExpires)).Methods("GET")
+	api.BaseRoutes.ApiRoot.Handle("/server_busy", api.ApiLocal(clearServerBusy)).Methods("DELETE")
 }