shader attributes naming fix

Runtime/Resources/UIWidgets_canvas_shadowBox.shader

         Pass {
             CGPROGRAM
             
-            float4 box;
+            float4 _sb_box;
-            float sigma;
-            float4 color;
+            float _sb_sigma;
+            float4 _sb_color;
             float _mat[9];
             
             struct appdata
             
             v2f vert(appdata v){
                 v2f o;
-                float padding = 3.0 * sigma;
-                o.coord = lerp(box.xy - padding, box.zw + padding, v.vertex.xy);
+                float padding = 3.0 * _sb_sigma;
+                o.coord = lerp(_sb_box.xy - padding, _sb_box.zw + padding, v.vertex.xy);
                 float3x3 mat = float3x3(_mat[0], _mat[1], _mat[2], _mat[3], _mat[4], _mat[5], 0, 0, 1);
                 float2 p = mul(mat, float3(o.coord.xy, 1.0)).xy - _viewport.xy;
                 
             }
             
             float4 frag(v2f i) : SV_TARGET {
-                float4 fragColor = color;
-                fragColor.a = fragColor.a * boxShadow(box.xy, box.zw, i.coord, sigma);
+                float4 fragColor = _sb_color;
+                fragColor.a = fragColor.a * boxShadow(_sb_box.xy, _sb_box.zw, i.coord, _sb_sigma);
                 return fragColor;
             }
             

Runtime/Resources/UIWidgets_canvas_shadowRBox.shader

         Pass {
             CGPROGRAM
             
-            float4 box;
+            float4 _sb_box;
-            float sigma;
-            float4 color;
-            float corner;
+            float _sb_sigma;
+            float4 _sb_color;
+            float _sb_corner;
             float _mat[9];
             
             struct appdata
             
             v2f vert(appdata v){
                 v2f o;
-                float padding = 3.0 * sigma;
-                o.coord = lerp(box.xy - padding, box.zw + padding, v.vertex.xy);
+                float padding = 3.0 * _sb_sigma;
+                o.coord = lerp(_sb_box.xy - padding, _sb_box.zw + padding, v.vertex.xy);
                 float3x3 mat = float3x3(_mat[0], _mat[1], _mat[2], _mat[3], _mat[4], _mat[5], 0, 0, 1);
                 float2 p = mul(mat, float3(o.coord.xy, 1.0)).xy - _viewport.xy;
                 
             }
             
             float4 frag(v2f i) : SV_TARGET {
-                float4 fragColor = color;
-                fragColor.a = fragColor.a * roundedBoxShadow(box.xy, box.zw, i.coord, sigma, corner);
+                float4 fragColor = _sb_color;
+                fragColor.a = fragColor.a * roundedBoxShadow(_sb_box.xy, _sb_box.zw, i.coord, _sb_sigma, _sb_corner);
                 return fragColor;
             }
             

Runtime/ui/renderer/cmdbufferCanvas/rendering/canvas_shader.cs

         static readonly int _mfKernelId = Shader.PropertyToID("_mf_kernel");
 
 
-        static readonly int _shadowBoxId = Shader.PropertyToID("box");
-        static readonly int _shadowSigmaId = Shader.PropertyToID("sigma");
-        static readonly int _shadowColorId = Shader.PropertyToID("color");
-        static readonly int _shadowCornerId = Shader.PropertyToID("corner");
+        static readonly int _shadowBoxId = Shader.PropertyToID("_sb_box");
+        static readonly int _shadowSigmaId = Shader.PropertyToID("_sb_sigma");
+        static readonly int _shadowColorId = Shader.PropertyToID("_sb_color");
+        static readonly int _shadowCornerId = Shader.PropertyToID("_sb_corner");
 
         static Vector4 _colorToVector4(uiColor c) {
             return new Vector4(