The helper renders French period labels (Janvier 2026, T2 2026, S1 2026),
so it carries the fr prefix like frDate. Config example, arch.md and
user-stories.md updated. Configs calling period(...) must switch to
frPeriod(...).
The generic emissionDate rule ran unconditionally: on a document whose
date is not numeric (e.g. "le 19 janvier 2026"), date(firstMatch(...))
errored on the empty match and routed a correctly classified document to
pending/. Each format probe now checks for its own format first, and a
frDate fallback handles French natural-language dates.
thomas