Until now, site configurations didn't have a JSON view for Browse and Read methods, and that made it impossible to manage site configurations from a client app.
We added those JSON views in the site settings component, and the code is in the master branch. We are still refining the output as we are developing the UX and UI in the Anahita React app, so we appreciate your patience until we tag ...
Just a reminder that #Anahita isn't yet compatible with PHP 7.4. The latest you can go to is PHP 7.3.9. The list of upgrades for PHP 7.4 is long, because of significant changes introduced in this release: https://github.com/php/php-src/blob/PHP-7.4/UPGRADING
We are working on it. If you can lend us a hand, we appreciate it, too.