add FamilyIDs to details document

onionoo has currently MyFamily support with multiple fields for that https://metrics.torproject.org/onionoo.html#details_relay_effective_family

c-tor gets Happy Family support in tpo/core/tor!857 (merged)

Please add the Happy Family FamilyID to the details document in a new details document field:

family_id array of strings

Array of Family IDs. Details can be found in Happy Families.

Example:

"family_id": ["YupI/ZI1z/u27VJADaCMftUsx51zT6atLD0Y2O9+XW8"]