refactor(modules): extract castopod parts into a modules/ folder for a scalable HMVC structure

- create Admin, Analytics, Auth, Fediverse and Install modules in the root modules/ folder
- rename
ActivityPub to Fediverse

app/Libraries/ActivityPub/Controllers/WebFingerController.php

@@ -1,32 +0,0 @@
-<?php
-
-declare(strict_types=1);
-
-/**
- * @copyright  2021 Podlibre
- * @license    https://www.gnu.org/licenses/agpl-3.0.en.html AGPL3
- * @link       https://castopod.org/
- */
-
-namespace ActivityPub\Controllers;
-
-use ActivityPub\WebFinger;
-use CodeIgniter\Controller;
-use CodeIgniter\Exceptions\PageNotFoundException;
-use CodeIgniter\HTTP\ResponseInterface;
-use Exception;
-
-class WebFingerController extends Controller
-{
-    public function index(): ResponseInterface
-    {
-        try {
-            $webfinger = new WebFinger($this->request->getGet('resource'));
-        } catch (Exception) {
-            // return 404, actor not found
-            throw PageNotFoundException::forPageNotFound();
-        }
-
-        return $this->response->setJSON($webfinger->toArray());
-    }
-}