Browser-safe endpoint routing preferences for query sessions.
Ingress takes none. QuestDB accepts writes on the primary alone: a replica,
or a primary still catching up, answers the /write/v4 upgrade with 421
and the role it holds, and the endpoint sweep moves on, so a sender reaches
the primary whatever role or zone it could ask for.
Browser-safe endpoint routing preferences for query sessions.
Ingress takes none. QuestDB accepts writes on the primary alone: a replica, or a primary still catching up, answers the
/write/v4upgrade with 421 and the role it holds, and the endpoint sweep moves on, so a sender reaches the primary whatever role or zone it could ask for.