Function dispatch_drag_start_to_script 

pub fn dispatch_drag_start_to_script<H: ScriptHost + Resource<Mutability = Mutable>>(
    host: ResMut<'_, H>,
    events: MessageReader<'_, '_, DragStarted>,
    ids: Query<'_, '_, &LumenId>,
    out: MessageWriter<'_, ScriptCommandEvent>,
)

Forward each DragStarted to the script as on_drag_start(source_id, payload).