[UI][Attachment] Use Attachment methods to get the proper URL, rather than crafting it in a template

plugins/ImageEncoder/ImageEncoder.php

@@ -143,9 +143,9 @@ class ImageEncoder extends Plugin
     public function onViewAttachmentImage(array $vars, array &$res): bool
     {
         $res[] = Formatting::twigRenderFile('imageEncoder/imageEncoderView.html.twig',
-            ['attachment'              => $vars['attachment'],
-                'thumbnail_parameters' => $vars['thumbnail_parameters'],
-                'note'                 => $vars['note'],
+            [
+                'attachment' => $vars['attachment'],
+                'note'       => $vars['note'],
             ]);
         return Event::stop;
     }

plugins/ImageEncoder/templates/imageEncoder/imageEncoderView.html.twig

@@ -1,6 +1,7 @@
 <figure>
-    <img class="u-photo" src="{{ path('attachment_thumbnail', thumbnail_parameters) }}"
-         alt="{{ attachment.getFilename() }}">
+    <img class="u-photo"
+         alt="{{ attachment.getBestTitle(note) }}"
+         src="{{ attachment.getThumbnailUrl() }}">
     <figcaption><a
                 href="{{ path('attachment_show', {'id': attachment.getId()}) }}">{{ attachment.getBestTitle(note) }}</a>
     </figcaption>