Modqueue: support variable size thumbnails

app/views/modqueue/_post.html.erb

@@ -1,6 +1,6 @@
 <%= tag.div id: "post-#{post.id}", **PostPreviewComponent.new(post: post).article_attrs("post mod-queue-preview column-container") do %>
   <aside class="column column-shrink">
-    <%= post_preview(post, show_size: true, show_deleted: true) %>
+    <%= post_preview(post, size: @preview_size, show_size: true, show_deleted: true) %>
   </aside>
 
   <section class="column column-expand">

app/views/modqueue/index.html.erb

@@ -11,7 +11,10 @@
 <% end %>
 
 <% content_for(:top_content) do %>
-  <h1>Moderation Queue</h1>
+  <div class="flex mb-4">
+    <h1 class="flex-grow-1">Moderation Queue</h1>
+    <%= render PreviewSizeMenuComponent.new(current_size: @preview_size) %>
+  </div>
 
   <div id="moderation-guideline" class="fixed-width-container">
     <h2>Deletion Guidelines</h2>