See title.
Rather than show the light bulb with 15, it shows the light bulb with 0 texture while when placed, it still places a light that outputs level 15.

/give @s light{BlockStateTag:{level:"-1"}}

Cause: in assets/minecraft/models/item/light.json, the selected texture is light_00.png, which is the light bulb 0 texture. The default texture should instead be set to light_15, as it places a level 15 light block, or it should place a light block with light level 0.

Relates to MC-222007.