Add pagination to the admin panel

[m4tx]

Currently, the admin panel displays all the objects on one page. We need to add pagination to avoid problems where there will be more than hundreds of rows in a table.

[ikorason]

Hi 👋 I would like to work on this if that's ok

[m4tx]

Sure, feel free to take it! Just as a little help where to start:

1. This first needs limit and offset params to be added to the Query structure as it doesn't currently support it
2. AdminModelManager::get_objects() (and hence also AdminModel::get_objects()) will need to take an object that contains said limit and offset and modify the Query object inside the derive macro accordingly

Feel free to ask if you need more help!