refactor: split frag0 into multiple files

default/frag6.glsl

@@ -1,4 +1,4 @@
-#include frag0.glsl
+#version 460
 
 // FX B
 // -------------
@@ -9,6 +9,13 @@
 in vec2 vUV;
 out vec4 fragColor;
 
+#include inc_fx.glsl
+
+uniform sampler2D iTex6;
+uniform sampler2D iTex8;
+uniform int iSeed6;
+uniform vec3 iMidi2_2[7];
+
 void main() {
     fragColor = fx_stage(vUV, iTex6, iTex8, iSeed6, iMidi2_2[0], iMidi2_2[1].xy, iMidi2_2[2], iMidi2_2[3].xy, iMidi2_2[4], iMidi2_2[5].xy, iMidi2_2[6]);
 }