[sso-admin] Add compatibility keys in outgoing API

dd-sso/admin/src/admin/lib/callbacks.py

@@ -36,6 +36,9 @@ def user_parser(dduser: DDUser) -> DDUser:
     user["keycloak_id"] = user.pop("id")
     user["role"] = user["roles"][0] if user.get("roles", []) else None
     user["groups"] = user.get("groups", user.get("keycloak_groups", []))
+    # Compatibility for the API
+    user["first"] = user["firstname"]
+    user["last"] = user["lasttname"]
     return user