friends query improvement

backend/src/routes/friends.js

@@ -60,10 +60,15 @@ router.get('/', authMiddleware, asyncHandler(async (req, res) => {
       FROM challenges c
       INNER JOIN challenge_participants cp ON cp.challenge_id = c.id
       WHERE cp.user_id = ? AND c.created_by != ? AND cp.status = 'accepted'
+      UNION
+      SELECT DISTINCT cp.user_id
+      FROM challenge_participants cp
+      INNER JOIN challenges c ON cp.challenge_id = c.id
+      WHERE c.created_by = ? AND cp.user_id != ? AND cp.status = 'accepted'
     )
     AND u.id NOT IN (${friends.map(() => '?').join(',') || 'NULL'})
     ORDER BY u.username`,
-    [req.user.userId, req.user.userId, req.user.userId, req.user.userId, ...friends.map(f => f.id)]
+    [req.user.userId, req.user.userId, req.user.userId, req.user.userId, req.user.userId, req.user.userId, ...friends.map(f => f.id)]
   );
 
   res.json({