[COMPONENT][Notification] Make logic more generic and robust

Fixed various bugs

Some important concepts to bear in mind:

* Notification: Associated with activities, won't be reconstructed
together with objects, can be thought of as transient

* Attention: Associated with objects, will be reconstructed with them, can
be thought as persistent

* Notifications and Attentions have no direct implications.

* Mentions are a specific form of attentions in notes, leads to the creation of Attentions.

Finally,

Potential PHP issue detected and reported: https://github.com/php/php-src/issues/8199
`static::method()` from a non static context (such as a class method) calls `__call`, rather than
the expected `__callStatic`. Can be fixed by using `(static fn() => static::method())()`, but the
usage of the magic method is strictly unnecessary in this case.

plugins/ActivityPub/Controller/Inbox.php

@@ -38,7 +38,6 @@ use function App\Core\I18n\_m;
 use App\Core\Log;
 use App\Core\Queue\Queue;
 use App\Core\Router\Router;
-use App\Entity\Actor;
 use App\Util\Common;
 use App\Util\Exception\ClientException;
 use Exception;
@@ -164,7 +163,7 @@ class Inbox extends Controller
 
         Queue::enqueue(
             payload: [$ap_actor, $actor, $type],
-            queue: 'activitypub_inbox',
+            queue: 'ActivitypubInbox',
             priority: false,
         );