ESPHome proxy for Switcher

I have a Switcher at home, which is a smart water heater controller. It lives in the IoT wifi jail, where they’re not allowed to reach to the open internet, and can only reply to requests from other devices (i.e. HomeAssistant).
My problem is and was that the Switcher updates state via UDP broadcasts, which don’t propagate to the HomeAssistant which lives in another subnet.
For years, I’ve been solving this by having the router run a udp-relay to pass the broadcast to regular network, but I don’t like it. The router setup is a bit hacky, and I’d like it to have as little responsibility aside from doing routing properly.
I yesterday had an idea. I already have some ESP32 devices in the IoT wifi, and some of them are configured with ESPHome to communicate with HomeAssistant. What if I got one of them to act as a Switcher proxy.

Got Claude Code to work on it, mainly translating the great work on aioswitcher. The result is Switcher-Proxy

Usage

external_components:
  - source:
      type: git
      url: https://github.com/backslasher/switcher-proxy
      ref: v1.0.0
    components: [switcher_proxy]

switcher_proxy:
  devices:
    - name: "Water Heater"
      # switcher_id: "aabbcc"  # omit to auto-discover first device
      power_sensor:
        name: "Water Heater Power"
      remaining_time_sensor:
        name: "Water Heater Time Remaining"

Very boring, but works. Well done original implementor for protocol, Claude for execution, and me for the idea.