greeting_trigger_node:
  ros__parameters:
    proximity_m: 2.0          # Trigger when person is within this distance (m)
    cooldown_s: 300.0         # Re-greeting suppression window per face_id (s)
    unknown_distance: 0.0     # Distance assumed when PersonState not yet available
                              # 0.0 → always greet faces with no state yet
    faces_topic: "/social/faces/detected"
    states_topic: "/social/person_states"
