Shelly sensor watchdog?

Hello

This is my first post. I am not so good in javascript. I hope to get to the right path with some help.

I have built a heating system on shelly devices. I have two zones of electrical underfloor heating, that consist of relays and flood sensors.

I also have 3 rooms with relays for radiators and H&T-s as sensors.

Today i discovered, that one flood had died. As a result underfloor heating had been on for 2 days straight. I changed the battery, and sensor became alive again. Now I need to figure something out that my underfloor heating would not get fried.

I tried to find an option that gives me alerts when battery-s run low, but I were not able to find any. Also something else might happen to sensors, so I thaught to have some redundant notifying option besides low battery notification.

I was thinking about a watcdog solution, where all relays have a script in them to ping corresponding sensor, and push notification (or email), when room sensor has been off for unreasonable time (like a day for example).

Would anybody have advice for me about how to achieve that. All I have found is a watcdog to restart a router, but not a solution like this.