Searches for a 32-byte LXMF stamp meeting stampCost for the given info
dict. Producer-side primitive — the full InterfaceAnnouncer is a follow-up;
exposed so tests can mint valid discovery announces.
Parameters
infoMap: Map<number,any>
OptionalstampCost: number = DEFAULT_STAMP_VALUE
OptionalexpandRounds: number = WORKBLOCK_EXPAND_ROUNDS
Searches for a 32-byte LXMF stamp meeting
stampCostfor the giveninfodict. Producer-side primitive — the fullInterfaceAnnounceris a follow-up; exposed so tests can mint valid discovery announces.