PII Shape Audit

Report personal-data shapes in structured logs, by field and class and never by value. A payment card is confirmed by the Luhn check and an account number by its own mod-97 checksum, so a match is a plausible real value rather than any digit run, which keeps an order number from being reported as a card. A date of birth needs a field named for one as well as a date. Each match reports its field, how many lines carry it and how many distinct values there are.