Add dark mode, i18n, messenger/moderation/verify, admin CRUD parity

Web-tier features completing the AtomCMS→Next.js conversion (slice 2):

UI/UX:
- Dark mode: html.dark CSS-var overrides + ThemeSwitcher (localStorage,
  no-flash boot script) wired into the nav.
- i18n (next-intl, cookie-based / no URL routing): en + it catalogs,
  request.ts, provider in root layout, LanguageSwitcher; shell (nav,
  header, footer) fully translated. URLs + access-guard unchanged.
- globals.css: --muted/--border aliases used across admin pages.

User features:
- /messages: offline messages + friend-request accept (server action
  re-reads session, two directional rows, idempotent).
- Email verification: signed-token /verify route + sendVerification wired
  into register (best-effort, never blocks signup).
- Article reactions: toggle UI on news/[slug] + server action.
- Content moderation service (website_wordfilter + optional OpenAI
  moderations, fail-open) wired into article comments + guestbook.

Admin CRUD parity (Filament replacement):
- /admin/shop (+ new/[id]) packages CRUD + read-only orders.
- /admin/transactions read-only PayPal log.
- /admin/permissions, /admin/tags, /admin/ads (+ new/[id]),
  /admin/help-questions (+ new/[id]), /admin/radio/history,
  /admin/users/[id]/edit. All gated by requireStaff + logStaffActivity.

Verified: tsc 0, vitest 48/48, next build 0 (all routes incl. new
admin CRUD + /messages + /verify).

src/components/site-header.tsx

@@ -1,9 +1,11 @@
+import { getTranslations } from "next-intl/server";
 import Link from "next/link";
 import { auth } from "@/lib/auth";
 import { prisma } from "@/lib/prisma";
 import { siteSettings } from "@/lib/services/site-settings";
 
 export async function SiteHeader() {
+  const t = await getTranslations("header");
   const [session, hotelName, header, logo] = await Promise.all([
     auth(),
     siteSettings.get("hotel_name", "Atom"),
@@ -50,7 +52,7 @@ export async function SiteHeader() {
                 style={{ backgroundColor: "var(--color-surface)" }}
               />
               <span className="relative">
-                {online} {hotelName} online
+                {t("online", { count: online, hotel: hotelName ?? "Atom" })}
               </span>
             </div>
           </div>
@@ -66,7 +68,7 @@ export async function SiteHeader() {
                   borderColor: "rgba(255,255,255,0.3)",
                 }}
               >
-                Nitro client
+                {t("nitroClient")}
               </button>
             </Link>
           </div>
@@ -77,10 +79,7 @@ export async function SiteHeader() {
             className="font-semibold flex flex-col items-center md:w-[600px]"
             style={{ color: "#ffffff", textShadow: "0 1px 4px rgba(0,0,0,0.7)" }}
           >
-            <p className="hidden text-center text-xl md:block">
-              An online virtual world where you can create your own avatar, make friends, chat,
-              create rooms and much more!
-            </p>
+            <p className="hidden text-center text-xl md:block">{t("tagline")}</p>
             <div className="flex flex-col items-center justify-center gap-x-6 gap-y-4 md:mt-6 md:flex-row md:gap-y-0">
               <Link href="/login">
                 <button
@@ -92,17 +91,17 @@ export async function SiteHeader() {
                     color: "var(--button-text-color)",
                   }}
                 >
-                  Login
+                  {t("login")}
                 </button>
               </Link>
-              <p className="text-sm uppercase">Or</p>
+              <p className="text-sm uppercase">{t("or")}</p>
               <Link href="/register">
                 <button
                   type="button"
                   className="uppercase px-8 py-2.5 rounded-full transition ease-in-out duration-200"
                   style={{ backgroundColor: "var(--color-accent)", color: "#ffffff" }}
                 >
-                  Create an account
+                  {t("createAccount")}
                 </button>
               </Link>
             </div>