v0.4.20 - Update Ambibox MQTT to hide car-related topics when EV unplugged

In this version:

SessionState is only advertised when EV is connected (PAUSED, STOPPED,
ERROR, CHARGE_LOOP). Car-related MQTT topics (soc, power, current,
sessionState, chargeProtocol) are cleared with empty payloads on unplug
and excluded from periodic publishing. Added error toggle for simulating
charger error state. UI controls are grayed out when unplugged and
state cards hide car-specific info.

Downloads

Platform	File	Requirements
macOS	device-simulator_darwin_amd64.zip	macOS 10.15+
Linux	device-simulator_linux_amd64.tar.gz	GTK3, WebKit2GTK
Windows	device-simulator_windows_amd64.zip	WebView2

Installation

macOS

1. Unzip and drag Device Simulator.app to Applications
2. Double-click to run (app is signed and notarized)

Linux

tar -xzf device-simulator_linux_amd64.tar.gz
sudo apt install libgtk-3-0 libwebkit2gtk-4.0-37  # Debian/Ubuntu
./linux/device-simulator.sh

Windows

1. Unzip and run Device-Simulator.bat or device-simulator.exe --desktop
2. WebView2 will auto-install if needed