clean test codes and unused scripts + rename folders

Runtime/RuntimeExample.cs

-// -----------------------------------------------------------------------------
-//
-// Use this runtime example C# file to develop runtime code.
-//
-// -----------------------------------------------------------------------------
-
-namespace Unity.UIWidgets {
-    /// <summary>
-    /// Provide a general description of the public class.
-    /// </summary>
-    /// <remarks>
-    /// Packages require XmlDoc documentation for ALL Package APIs.
-    /// https://docs.microsoft.com/en-us/dotnet/csharp/programming-guide/xmldoc/xml-documentation-comments
-    /// </remarks>
-    public class MyPublicRuntimeExampleClass {
-        /// <summary>
-        /// Provide a description of what this private method does.
-        /// </summary>
-        /// <param name="parameter1"> Description of parameter 1 </param>
-        /// <param name="parameter2"> Description of parameter 2 </param>
-        /// <param name="parameter3"> Description of parameter 3 </param>
-        /// <returns> Description of what the function returns </returns>
-        public int CountThingsAndDoStuff(int parameter1, int parameter2, bool parameter3) {
-            return parameter3 ? (parameter1 + parameter2) : (parameter1 - parameter2);
-        }
-    }
-}

Runtime/RuntimeExample.cs.meta

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Tests.meta

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