fix(codegen): Reverts & Disables codegen (for now) (#625)

After speaking with the C# devs, it is clear that code gen is not ready.
I can get around this by doing the following:
1. Creating a library
2. Splitting out the schema writing from the source generator
3. Moving the schema loading to `AdditionalFiles`
4. Writing a new post-build application using Roslyn to write the schema files after building.

Projects/SerializationGenerator/EntitySerializationGenerator.cs

@@ -27,13 +27,6 @@ namespace SerializationGenerator
     {
         public void Initialize(GeneratorInitializationContext context)
         {
-#if DEBUG
-            if (!Debugger.IsAttached)
-            {
-                Debugger.Launch();
-            }
-#endif
-
             context.RegisterForPostInitialization(i =>
             {
                 SerializerSyntaxReceiver.AttributeTypes.Add("Server.SerializableAttribute");