从 2.3.x 升级到 5.x 失败: api_token_scopes 迁移加载了尚不存在的列/表,通过 access_scopes → spawner.user

In upgrade(), the oauth_clients loop calls access_scopes(oauth_client, db), and access_scopes accesses spawner.user.name:

spawner = oauth_client.spawner
if spawner:
…