NativeListReprRules

find: List[A] → (A → Boolean) → Option[A]. For non-PackedData (native-element) sources, declare SumUplcConstr Option so callers stay in native flow; otherwise fall back to the type's default. The dispatcher converts at the boundary (one element max).

foldLeft: List[A] → B — output depends on return type

foldRight: same as foldLeft

map/filter/etc: after self substitution, outTp is the remaining curried function. Use defaultRepresentation which handles Fun types correctly.