Remove activity stream functionality from controllers and providers.

- Remove activity stream related code and files
- Update configuration for HtmlSanitizer and RetryGuzzle
- Add `paginate` macro for `Collection`
- Remove unused code for `Codebird`
- Simplify `FrontPageController` and `NotesController` methods

app/Services/ActivityStreamsService.php

@@ -1,59 +0,0 @@
-<?php
-
-declare(strict_types=1);
-
-namespace App\Services;
-
-use App\Models\Note;
-use Illuminate\Http\Response;
-
-class ActivityStreamsService
-{
-    /**
-     * Return the relevant data to an AS2.0 request to the root path.
-     */
-    public function siteOwnerResponse(): Response
-    {
-        $data = json_encode([
-            '@context' => 'https://www.w3.org/ns/activitystreams',
-            'id' => config('app.url'),
-            'type' => 'Person',
-            'name' => config('user.displayname'),
-            'preferredUsername' => config('user.username'),
-        ]);
-
-        return response($data)->header('Content-Type', 'application/activity+json');
-    }
-
-    /**
-     * Return the relevant data to an AS2.0 request for a particular note.
-     */
-    public function singleNoteResponse(Note $note): Response
-    {
-        $data = json_encode([
-            '@context' => 'https://www.w3.org/ns/activitystreams',
-            'summary' => strtok(config('user.displayname'), ' ') . ' added a note to their microblog',
-            'type' => 'Add',
-            'published' => $note->updated_at->toW3cString(),
-            'actor' => [
-                'type' => 'Person',
-                'id' => config('app.url'),
-                'name' => config('app.display_name'),
-                'url' => config('app.url'),
-                'image' => [
-                    'type' => 'Link',
-                    'href' => config('app.url') . '/assets/img/profile.jpg',
-                    'mediaType' => '/image/jpeg',
-                ],
-            ],
-            'object' => [
-                'id' => $note->longurl,
-                'type' => 'Note',
-                'url' => $note->longurl,
-                'name' => strip_tags($note->note),
-            ],
-        ]);
-
-        return response($data)->header('Content-Type', 'application/activity+json');
-    }
-}