How to Sync Vendor Location to Listings

It’s very interesting @shibfox !

What if I want to preset (sync) the listing category with the one from the vendor, instead of geolocation (it’s a digital services marketplace, location does not matter) ?
I tried to customize your code, like so :

add_filter(
    'hivepress/v1/models/listing/attributes',
    function( $attributes ) {
        if ( isset( $attributes['category'] ) ) {
            $attributes['category']['synced'] = true;
        }
        return $attributes;
    },
    1000
);

but it does nothing.

Thanks !