Six post-definition dict-set! calls add .length=1 and .name="<Ctor>"
to the global constructor dicts. Per spec Number/String/Array/Boolean/
Object all have length 1 (they take one arg).
Unit 521/522, slice 148/148 unchanged.
Number scoreboard: 52/100 → 53/100 (+1, S15.7.3_A8: Number.length==1).