Updates required for ESPHome 2026.8.0

[tomlut]

Heads up!

The next release of esphome updates the sen5x platform:

https://beta.esphome.io/changelog/2026.8.0/

If you use voc or nox sensor keys on sgp4x, sen5x or sen6x, rename them to voc_index and nox_index

[bharvey88]

Thanks for the heads up! Fix is up in #124.

Fun fact: that upstream rename is actually mine (esphome/esphome#17724). The bare voc/nox keys read like concentration sensors when what they publish is Sensirion's unitless gas index (1-500, baseline 100), so I renamed them to match what they actually are. The old keys keep working with a deprecation warning until 2027.2.0, so nothing breaks in the meantime either way.