Was looking for something like this but stumbled upon herdr-web-ui [0] first. They seem to do the same thing, but herdr-web-ui is completely free and self hosted and sets up as a PWA with webpush support. Seems to work decently well and it’s under heavy development. Will have to try this too!
If you are in the Herdr ecosystem and the iOS ecosystem I highly recommend Heeler: https://github.com/ZingerLittleBee/Heeler