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/record-settings/configuration.ts

@@ -11,6 +11,7 @@ import {
   WRITABLE_MODULE_KEYS,
 } from "@/lib/validations/modules";
 import { thresholdsUpdateSchema } from "@/lib/validations/thresholds";
+import { locales } from "@/lib/i18n/config";
 
 /**
  * The target-record configuration boundary. These literals are both the DTO
@@ -60,10 +61,7 @@ const profilePatchSchema = z
     heightCm: z.number().finite().min(30).max(300).nullable().optional(),
     dateOfBirth: z.string().date().nullable().optional(),
     gender: z.enum(["MALE", "FEMALE", "OTHER"]).nullable().optional(),
-    locale: z
-      .enum(["de", "en", "es", "fr", "it", "pl", "ko", "nl"])
-      .nullable()
-      .optional(),
+    locale: z.enum(locales).nullable().optional(),
     timezone: timezoneSchema.optional(),
     unitPreference: z.enum(["metric", "imperial"]).optional(),
     timeFormat: z.enum(["AUTO", "H12", "H24"]).optional(),