hermes
6e1189e319
The round-2 review noted that `_upgrade_password` catches `PyMongoError` without logging it. A failed upgrade is harmless to the login itself - the user still gets in - but it leaves the password stored in plain text, and that is exactly the kind of thing an operator needs to know about. It is now logged as a warning with the username and the traceback. A test covers the path: the migration write is forced to fail, the login still succeeds, and the warning is emitted.