Custom item lightning not in hand

[Globox1997]

Is your feature request related to a problem? Please describe. Mods which add items like the classic mining helmet do not render dynamic light when equipped.

Describe the solution you'd like Dynamic lightning should get activated when a certain slot contains a certain item. Those should get defined in code.

Describe alternatives you've considered

Additional context Open PR with custom item lightning when item is held in hand https://github.com/IrisShaders/Iris/pull/1563