getAttendeeNamesByIds(ids: number[],privateKey: CryptoKey,): Promise<Map<number, string>>
Bounded id → name lookup for the given attendees, decrypting only the name from each PII blob with the owner private key (no booking join, one row per attendee). Empty ids ⇒ empty map. Used for link labels in the activity log; a deleted attendee's id simply has no entry.
privateKey: CryptoKey