@hk24 in the node_helper you could extend the routes of the express server so when you click the link there will be a request send to your node_helper script which can then activate the lightbulb.
see an example here https://github.com/paviro/MMM-syslog/blob/master/node_helper.js#L17
the link would look like this http://MIRROR_IP:MIRROR_PORT/syslog?type=INFO&message=YOUR_MESSAGE