add missing datastore index for /recent with ?after query param

index.yaml

@@ -6,6 +6,11 @@ indexes:
 # index.yaml file manually, remove the "# AUTOGENERATED" marker line above.
 # If you want to manage some indexes manually, move them above the marker line.
 
+- kind: Response
+  properties:
+  - name: status
+  - name: updated
+
 - kind: Response
   properties:
   - name: status