Make role objects to pivot models

[kdmnk]

see here: https://laravel.com/docs/8.x/eloquent-relationships#defining-custom-intermediate-table-models (idk whether it is good for us)

[luksan47]

Might be if we are using it as often as we use roles. Worth some time to investigate.

[kdmnk]

I just find it unneccessary (and strange) if we are making models (sort of) from these objects anyways (see toSelectableCollection function).