Allow emitting arrays as TS tuples

[akx]

pub(crate) struct Scene {
    color: [f32; 4],
}

currently becomes an array of uncertain length,

export interface Scene { 
  color: Array<number>;
}

It would be useful to be able to mark this e.g.

pub(crate) struct Scene {
    #[ts(tuple)]
    color: [f32; 4],
}

to emit it as

export interface Scene { 
  color: [number, number, number, number];
}

I tried my hand at implementing this myself, but got lost in macros...