The three locale matchers were built in parallel and each grew its own
fold. Two of them are the same function: the side-effect tag fold and
foldForMatch agree character for character, so one now calls the other.
The third stays. foldLabel decomposes with NFKD, maps sharp s to ss and
joins with underscores; foldForMatch decomposes with NFD, leaves sharp s
alone and joins with spaces. That is a disagreement about who typed the
text, not an accident: one side of a lab comparison is a shipped label
retyped or prose a lab printed, where tolerating a different spelling
claims more than the fold can prove, while someone naming a metric to an
assistant is composing rather than reproducing. Both docblocks now say
so and name the other.