Added Unity project files

Packages/com.vrchat.worlds/Integrations/ClientSim/Runtime/Utilities/ClientSimException.cs

@@ -0,0 +1,12 @@
+using System;
+
+namespace VRC.SDK3.ClientSim
+{
+    /// <summary>
+    /// A wrapper for exceptions that can easily be checked in Tests.
+    /// </summary>
+    public class ClientSimException : Exception
+    {
+        public ClientSimException(string message) : base(message) { }
+    }
+}