Switch to TG hair sprites.

This removes the need for a separate shader because they're multiply-based instead of additive like /vg/ or Bay.

Resources/Shaders/hair.swsl

@@ -1,8 +0,0 @@
-// Additively blends the hair color onto the hair sprite.
-
-uniform vec4 hairColor;
-
-void fragment() {
-    COLOR = texture(TEXTURE, UV);
-    COLOR.rgb += hairColor.rgb;
-}