i18n: translate all public page bodies (EN + IT)

Internationalised the ~44 public pages with next-intl (the shell was
already translated). Each page now pulls its copy from a "pages.<slug>"
namespace via getTranslations (server) / useTranslations (client); the
EN + IT catalogs were authored by parallel agents and merged centrally,
with natural Italian (ICU plurals) and it backfilled from en for any
gap. request.ts gained getMessageFallback/onError so a missing key
degrades to the English value, never a raw key.

Behaviour unchanged (only display text moved to t() calls; queries,
actions, fields, ContentCard structure preserved). Verified on the prod
server: with NEXT_LOCALE=it, home/community/staff/news/shop/rankings all
render Italian copy, no raw-key leakage; English unchanged. The nav
language switcher toggles EN/IT live. tsc 0, vitest 49/49, next build 0.

Admin pages intentionally left in English (staff tooling).

src/app/radio/contests/page.tsx

@@ -1,3 +1,4 @@
+import { getTranslations } from "next-intl/server";
 import Link from "next/link";
 import { ContentCard, EmptyState } from "@/components/public/ui";
 import { prisma } from "@/lib/prisma";
@@ -9,6 +10,8 @@ function formatDate(d: Date | null | undefined): string {
 }
 
 export default async function RadioContestsPage() {
+  const t = await getTranslations("pages.radioContests");
+
   // RadioContests.id is a BigInt — stringify before use in keys/routes.
   const contests = await prisma.radioContests
     .findMany({
@@ -21,13 +24,13 @@ export default async function RadioContestsPage() {
     <main style={{ display: "grid", gap: "1.5rem" }}>
       <ContentCard
         icon="🎉"
-        title="Radio Contests"
-        subtitle="Tune in and take part in our latest on-air contests"
+        title={t("title")}
+        subtitle={t("subtitle")}
       />
 
       <ContentCard padded={contests.length === 0}>
         {contests.length === 0 ? (
-          <EmptyState icon="🎉">No contests yet.</EmptyState>
+          <EmptyState icon="🎉">{t("empty")}</EmptyState>
         ) : (
           <div className="card-grid sm-2 lg-3" style={{ padding: "1rem" }}>
             {contests.map((c) => {
@@ -40,10 +43,10 @@ export default async function RadioContestsPage() {
                   style={{ color: "inherit", textDecoration: "none", display: "grid", gap: "0.3rem" }}
                 >
                   <h3 style={{ margin: 0, fontSize: "1rem" }}>
-                    <span aria-hidden>🎉</span> Contest #{id}
+                    <span aria-hidden>🎉</span> {t("contestLabel", { id })}
                   </h3>
                   <p className="muted" style={{ margin: 0 }}>
-                    {formatDate(c.createdAt) || "Date unknown"}
+                    {formatDate(c.createdAt) || t("dateUnknown")}
                   </p>
                 </Link>
               );