fix: one more endpoint

app/routes/index.js

@@ -193,7 +193,7 @@ router.get('/groupchats/:target', async function (req, res) {
           groupInfo.updated = dres.rows[0].updated;
           res.send(JSON.stringify(groupInfo));
         } else {
-          res.status(404).json(null);
+          res.status(410).json({status:"groupchat not found - probably deleted"});
         }
       } else {
         res.status(500).json(derr);