feat(i18n): register Brazilian Portuguese as a locale

Add pt-BR to the locale list and everything that hangs off it: the
client loader, Intl and date-fns mapping, the reply-language footers of
the Coach and insights prompts (English body, pt-BR footer, the same
path Korean and Dutch take), the citation-coverage normative words, the
no-key fallback copy, the AUDIT-C standard-drink line, country labels,
period search, CSV yes/no cells and the Telegram bare-word aliases.

The locale enums in the extract, managed-profile and record-settings
schemas now derive from the locale list instead of repeating it, and
the five notification and login-alert routes share one isLocale guard
instead of hand-rolled chains, so a later locale is one edit there.
A language tag is matched exactly and case-insensitively before its
primary subtag, so pt-BR and pt-PT browsers land on the Portuguese
bundle rather than English, and AUDIT-C no longer cuts a region tag to
two letters.

PHQ-9, GAD-7 and WHO-5 are not marked validated for pt-BR: the wording
has not been read against the published Brazilian forms, so readers get
the English items plus the existing note.

src/lib/profile/country-label.ts

@@ -17,6 +17,7 @@ const NAMES: Readonly<Record<string, Readonly<Record<SourceCountry, string>>>> =
     pl: { DE: "Niemcy", KR: "Korea Południowa", US: "Stany Zjednoczone" },
     nl: { DE: "Duitsland", KR: "Zuid-Korea", US: "Verenigde Staten" },
     ko: { DE: "독일", KR: "대한민국", US: "미국" },
+    "pt-BR": { DE: "Alemanha", KR: "Coreia do Sul", US: "Estados Unidos" },
   };
 
 export function countryLabel(