CAS locked in → PubChem lookup fires
                        ↓
           ┌────────────┴────────────┐
     PubChem has name?             No name
           ↓                          ↓
    AI has name?              keep AI name (if any)
    ┌───────┴───────┐         aiSatisfied = !aiName.isEmpty
   Yes             No
    ↓               ↓
 arbitrate       use PubChem name directly
    ↓               aiSatisfied = true
 isSameCompound?
  ┌────┴────┐
 Yes       No
  ↓         ↓
 labelIsCommonName?   trust PubChem (CAS is reliable)
  ┌────┴────┐
 Yes       No
  ↓         ↓
 use        use
 label      PubChem
 name       name
 ("CHAPS")
aiSatisfied = true → no more AI re-triggers