Control and Automate Air Purifier with ESP32 and Home Assistant Air Quality Index

I’ve always been a bit obsessive about air quality. Living in a city, you notice the difference a good air purifier makes, but I got tired of manually turning it on every time the pollution levels spiked. It felt, well, decidedly un-smart. So I set out to fix that by creating a system where my air purifier automatically kicks in when the Home Assistant Air Quality Index (AQI) reaches a certain threshold.