Since Nothing OS 2.0 has this functionality built in (long press on the torch quick toggle) this repo could be considered obsolete.
GlyphTorch wraps around the preinstalled led test app to make using the glyph interface as a torch way easier by adding a quick settings tile. This app was built for the Nothing Phone (1). It might work with future Nothing phones (if they still have the led test app preinstalled).
Starting with Android 13, your phone may not let you enable the accessibility service by default. In that case, you can just head to the app info page, click on the three dots, and enable restricted settings from there.