`GodotConvert` derive-macro and `godot(transparent)` with `PhantomData`

[ProphetOSpam]

It should be possible to derive GodotConvert with godot(transparent) on structs that have PhantomData and generics.

For example:

#[derive(GodotConvert)]
#[godot(transparent)]
pub struct Id<T>(u32, PhantomData<T>);

This struct is basically a newtype around u32 with some extra rust typing, and so it makes sense that this should be representable in Godot.

[ProphetOSpam]

Note: The docs currently say:

However, [transparent] will not work for structs with more than one field, even if that field is zero sized

I'm not sure if there's a technical reason for this; I didn't find any after looking through the relevant code, but I'm new to this codebase, and I may have missed something.

[ProphetOSpam]

My current solution is wrapping Id<T> in a newtype without generics and writing From impls, like:

#[derive(GodotConvert)]
pub struct GId(u32);

impl<T> From<Id<T>> for GId {
    fn from(value: Id<T>) -> GId {
        Self(value.0)
    }
}

impl<T> From<GId> for Id<T> {
    fn from(value: GId) -> Id<T> {
        Self(value.0, PhantomData)
    }
}

Another solution would be to implement GodotConvert, ToGodot and FromGodot manually.

However, both of these are a lot of boilerplate which I would rather avoid