Interrupt LED doesn't work

According to the [datasheet](https://cdn-learn.adafruit.com/downloads/pdf/adafruit-ano-rotary-navigation-encoder-to-i2c-stemma-qt-adapter.pdf), apart from the power LED, there is another LED on the board.

> Interrupt LED - On the back of the board below the STEMMA QT port on the left is the interrupt LED. It is the red LED and turns on whenever an interrupt is detected.

But when I press the buttons or rotate the wheel, nothing happens.

What am I doing wrong?

Start with the linked Adafruit ANO Rotary Navigation Encoder datasheet and reproduce the button-press and wheel-rotation behavior described in the issue. Check the repository's Python driver entry points for interrupt handling and determine whether the LED behavior is expected or indicates a driver or hardware problem; done means documenting the cause and a reproducible fix or configuration.

Written by the indexing model from the issue text.