Returns the referral relationships for the specified person, showing advocate-friend connections created through campaign participation. Each entry carries the requested person's my_role (ADVOCATE or FRIEND) and the other_person_id on the other side, rather than being split into fixed advocate and friend collections.

Each entry also carries other_person, resolving that person to this client's identity_key and identity_key_value, so a whole network can be labelled from one request rather than one request per related person. A relationship always names another person, so other_person is always present.

Relationships are de-duplicated by identity, keeping the most recent one per related person, unless include_duplicate_identities is set. When collapsing persons yourself, key on identity_key_value, falling back to other_person_id when the person has no identity key value yet. Never key on email: clients whose identity key is not email routinely have many distinct persons sharing an email or having none, so collapsing on email under-reports the network.