Membership ids exactly as the search returned them (quirk #5). Kept for diagnostics, and as the input labelNames is resolved from.
The account's CURRENT label names, resolved from labelIds. Every
label write must start from this set or it clobbers the account's other
memberships (quirk #1). An id with no matching label is dropped rather
than passed through — a raw id inside a label_names write would create a
junk label named after a hex string.
Apollo's primary_domain; '' when absent.
An account from the saved-account search. Deliberately thin: a list-cleanup workflow needs the identity, the domain for triage, and — load-bearing — the current label set, so a move can preserve it. Apollo returns far more fields and they are not modelled.