Very naively, inspired by the other discussion as well as Present Time Range in Grafana's Text Panel - Stack Overflow, I tried
angular.element('grafana-app').injector().get('timeSrv').refresh = '5s';
While the value was set successfully, it did not have any effect on the actual dashboard behavior.
I suspect that the above is no longer a viable approach in 7.x, with the migration to React? Is there still a reasonable way to achieve what I’m attempting?