1.21.5 support

[Agaloth]

I fixed fancypants for 1.21.5 by making the shader use entity instead of rendertype_armor_cutout_no_cull which works on most servers but it's really unsafe and can break some stuff on some servers, would you have any recommendations? I'll attach the modified shaders below (can't attach .fsh and .vsh files but the files are just renamed to entity instead of rendertype_armor_cutout_no_cull), the json is what's modified to make it work atm:

I'm not a shader dev so some stuff might be wrong but this is what worked for most servers

entity.json