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/shop/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 { excerpt } from "@/lib/format";
@@ -53,6 +54,7 @@ export default async function ShopPage({
 }: {
   searchParams: Promise<{ category?: string }>;
 }) {
+  const t = await getTranslations("pages.shop");
   const sp = await searchParams;
   const rawCategory = (sp.category ?? "").trim();
   const categoryId = /^\d+$/.test(rawCategory) ? rawCategory : "";
@@ -110,11 +112,11 @@ export default async function ShopPage({
     <main style={{ display: "grid", gap: "1.5rem" }}>
       <ContentCard
         icon="🛒"
-        title="Shop"
+        title={t("title")}
         subtitle={
           activeCategory
-            ? `Browsing the ${activeCategory.name} packages.`
-            : "Top up your account and grab exclusive packages, currency and badges."
+            ? t("browsingCategory", { category: activeCategory.name })
+            : t("subtitle")
         }
       >
         {categories.length > 0 ? (
@@ -126,7 +128,7 @@ export default async function ShopPage({
             }}
           >
             <Link href="/shop" className={`btn ${categoryId ? "btn-outline" : "btn-primary"}`}>
-              All
+              {t("all")}
             </Link>
             {categories.map((c) => (
               <Link
@@ -143,16 +145,16 @@ export default async function ShopPage({
 
       <ContentCard
         icon="📦"
-        title={activeCategory ? activeCategory.name : "All packages"}
+        title={activeCategory ? activeCategory.name : t("allPackages")}
         subtitle={
           articles.length > 0
-            ? `${articles.length} ${articles.length === 1 ? "package" : "packages"} available`
+            ? t("packagesAvailable", { count: articles.length })
             : undefined
         }
         padded={articles.length === 0}
       >
         {articles.length === 0 ? (
-          <EmptyState icon="🛒">No packages available right now.</EmptyState>
+          <EmptyState icon="🛒">{t("empty")}</EmptyState>
         ) : (
           <div className="card-grid sm-2 lg-3" style={{ padding: "1rem" }}>
             {articles.map((a) => (
@@ -237,7 +239,7 @@ export default async function ShopPage({
                 >
                   <span style={{ fontWeight: 800 }}>{priceLabel(a.costs)}</span>
                   <span className="btn btn-primary" aria-disabled="true">
-                    Buy
+                    {t("buy")}
                   </span>
                 </div>
               </article>