Typed error instance — instanceof TerminalError (4xx) or instanceof TransientError (5xx/network).
True when the last attempt ended with any error (terminal or transient).
True only while the very first attempt is in-flight with no cached rows yet.
Resolved entity rows in the graph for this query, in server order.
Manually trigger a fresh fetch (bypasses staleTime).
Five-field return — the entirety of what a list consumer needs for the common case.