max / goingson

Let a backup holding a sync account read back SyncAccount.user_id was skip_serializing with no default, so the field was absent from the JSON and had nothing to deserialize into. Any backup containing at least one sync account failed on read, which meant restore failed exactly for the users who had configured sync. Pre-existing and independent of the write path: the same file written by the old write_backup was equally unreadable. Found by a round-trip test seeding every collection. Matches the house pattern already on SavedView.user_id, where restore re-homes the row to the target user so the deserialized placeholder is never persisted.