fix: multiple createdAt columns in query causes conflicts (#3506)

* test: list posts with mentions filter and `createdAt` sort
* fix: multiple `createdAt` columns in query causes conflicts
* chore: link to pull request for context

Signed-off-by: Sami Mazouz <ilyasmazouz@gmail.com>

framework/core/src/Api/Controller/ListPostsController.php

@@ -113,6 +113,20 @@ class ListPostsController extends AbstractListController
         return $results;
     }
 
+    /**
+     * @link https://github.com/flarum/framework/pull/3506
+     */
+    protected function extractSort(ServerRequestInterface $request)
+    {
+        $sort = [];
+
+        foreach ((parent::extractSort($request) ?: []) as $field => $direction) {
+            $sort["posts.$field"] = $direction;
+        }
+
+        return $sort;
+    }
+
     /**
      * {@inheritdoc}
      */