Change default for tsync

[Wulf]

After thinking about this for some time, I've come to the conclusion that #[tsync] additions shouldn't be the default like it currently is. Users should manually copy and edit the generated read struct and filter out any properties that may contain sensitive information not bound for the frontend

[hasezoey]

some extra context, currently the tsync feature is enabled by default, but would still require using --tsync(argument) to actually generate #[tsync] derives.