move unity package to the root

Samples~/SamplesBuiltin/Shaders/MixboxSampleShader.shader

@@ -0,0 +1,45 @@
+Shader "Mixbox/Mixbox Sample Shader"
+{
+    Properties
+    {
+        [NoScaleOffset] _MixboxLUT ("Mixbox LUT", 2D) = "white" {} // assign "Packages/Mixbox/Textures/MixboxLUT.png"
+        
+        _Color1 ("Color 1", Color) = (0, 0.129, 0.522, 1) // blue
+        _Color2 ("Color 2", Color) = (0.988, 0.827, 0, 1) // yellow
+    }
+    SubShader
+    {
+        Pass
+        {
+            CGPROGRAM
+            #pragma vertex vert
+            #pragma fragment frag
+
+            #include "UnityCG.cginc"
+
+            sampler2D _MixboxLUT;
+            #include "Packages/com.scrtwpns.mixbox/ShaderLibrary/Mixbox.cginc"
+
+            fixed4 _Color1;
+            fixed4 _Color2;
+            
+            struct appdata { float4 vertex : POSITION; float2 uv : TEXCOORD0; };
+            struct v2f { float2 uv : TEXCOORD0; float4 vertex : SV_POSITION; };             
+
+            v2f vert (appdata v)
+            {
+                v2f o;
+                o.vertex = UnityObjectToClipPos(v.vertex);
+                o.uv = v.uv;
+                return o;
+            }
+
+            fixed4 frag (v2f i) : SV_Target
+            {
+                fixed4 mixedColor = MixboxLerp(_Color1, _Color2, i.uv.x);
+                return mixedColor;
+            }
+            ENDCG
+        }
+    }
+}

Samples~/SamplesBuiltin/Shaders/MixboxSampleShader.shader.meta

@@ -0,0 +1,10 @@
+fileFormatVersion: 2
+guid: bb6490bc8e0170a40a722ad60ca9e82d
+ShaderImporter:
+  externalObjects: {}
+  defaultTextures: []
+  nonModifiableTextures: []
+  preprocessorOverride: 0
+  userData: 
+  assetBundleName: 
+  assetBundleVariant: