Replays gpt61/upstream-station (#1381) onto the Desktop stack: a node started with --upstream-station delegates OAuth to the station's oatproxy (streamplace/oatproxy#12), indexes only accounts with a completed local OAuth session, and takes their events from per-DID atmoq tracks. #1381 was closed when Desktop was rebooted as a single-user app; its chained OAuth and indexing gate are what that app needs to keep users logged in and to stay off other accounts' PDSes.