fix expression editor and migration

Assets/VRM10/Runtime/Components/Expression/MorphTargetBinding.cs

@@ -16,9 +16,11 @@ namespace UniVRM10
         /// * モデル変更時の改変への強さ
         /// 
         /// </summary>
-        public readonly String RelativePath;
-        public readonly int Index;
-        public readonly float Weight;
+
+        // シリアライズしてEditorから変更するので readonly 不可
+        public /*readonly*/ String RelativePath;
+        public /*readonly*/ int Index;
+        public /*readonly*/ float Weight;
 
         /// <summary>
         /// 

Assets/VRM10/Runtime/Migration/Migration.cs

@@ -445,7 +445,7 @@ namespace UniVRM10
             {
                 var meshIndex = x["mesh"].GetInt32();
                 var morphTargetIndex = x["index"].GetInt32();
-                var weight = x["weight"].GetInt32() * 0.01f;
+                var weight = x["weight"].GetInt32();
 
                 var bind = new UniGLTF.Extensions.VRMC_vrm.MorphTargetBind();