feat: harden atoms-nexst against review findings (37 items)

Second review pass covering security, performance, admin tooling and the
public/room flows. All HIGH and MEDIUM findings from the audit are resolved;
nothing in this commit changes the visible feature set.

Authentication & session security
- CSP is now set on the request headers in the proxy, which is what Next.js
  uses to derive the render nonce, so the nonce is effective.
- 2FA: an already-enabled user cannot re-enroll, the setup endpoint is
  rate-limited per account, and confirmed codes are persisted so the second
  secret no longer silently never applies.
- Password reset revokes the ticket, authTicket and all personal access
  tokens, and bumps the token version so existing sessions die. The same
  revocation is now wired into the staff-side password reset.
- /reset and /verify return a stable error code instead of raw text; the
  mail lookups are ordered by id so duplicates cannot vary between runs.
- Resending the verification mail gets a per-address cooldown on top of the
  per-user limit.
- Issue API tokens with the narrower radio/ticket ability set instead of "*".

Authorization & input handling
- Mid-rank staff can no longer keep dynamically granted non-view admin.*
  permissions: existing grants are revoked by migration and the grant lookup
  is restricted to "%.view". Rank guards use the dynamic super-admin check.
- Alerting a user is permission-checked and audited like the other tools.
- Material mutations (giveCredits/giveDuckets/giveDiamonds, the admin user
  actions route, bulk user actions) are capped and rank-guarded, and bulk
  ids are bounded.
- updateRoom / updateRoomItem write through a field allowlist, and items
  may only be edited through their own room.
- Classnames reaching the filesystem are validated before use so a crafted
  value cannot escape the asset directories.
- The word filter now also covers offline mails, guild forum threads and
  replies, and user mottos.
- Media uploads are validated by magic bytes, /api/media requires the page
  edit permission, APP_URL must be configured once mail is enabled, and the
  diagnostics error route checks the fetch site header.

Admin tooling
- Secret settings render masked and cannot be overwritten with a blank or
  an arbitrary raw key; radio credentials are new password inputs.
- Commandocentrum balance changes are audited.
- Admin list pagination reads the caller's per-page instead of the max, and
  the log exporter caps offset and search length.

Performance
- Catalog translations are cached per module, with a cheap revision hash;
  the public online count uses a stale window instead of hammering the DB.
- The cache warmup now primes the payload the home route actually reads.
- TopHeader batches its queries into one round trip, and LCP avatars load
  eagerly.
- motion/react and sonner are no longer part of the root layout; the nav
  dropdown and mobile nav panels are lazy client chunks. Anonymous visitors
  again get the navigation chrome, and public pages get an edge cacheable
  response.

Accessibility
- Nested <main> elements in phase pages became <section>; the page entrance
  and route progress animations are pure CSS that respect reduced motion.

src/app/(site)/page.tsx

@@ -1,4 +1,4 @@
-import { count, desc, eq } from "drizzle-orm";
+import { desc, eq } from "drizzle-orm";
 import { ArrowRight, ChevronDown } from "lucide-react";
 import type { Metadata } from "next";
 import { headers } from "next/headers";
@@ -25,7 +25,9 @@ import { formatDate } from "@/lib/format-date";
 import { resolveHotelName } from "@/lib/hotel-name";
 import { captchaConfig } from "@/lib/services/captcha";
 import { getNewsList } from "@/lib/services/news-list";
+import { loadProfilePrivacyMap } from "@/lib/services/profile-privacy";
 import {
+	cachedOnlineCount,
 	countArticles,
 	countPhotos,
 	countRooms,
@@ -183,13 +185,7 @@ async function getHotelData() {
 		recentUsers,
 		recentPhotos,
 	] = await Promise.all([
-		cached("online_count", 10_000, () =>
-			db
-				.select({ total: count() })
-				.from(User)
-				.where(eq(User.online, "1"))
-				.then((rows) => rows[0]?.total ?? 0),
-		).catch(publicReadFailure("home.online")),
+		cachedOnlineCount().catch(publicReadFailure("home.online")),
 		cached("total_users", 300_000, countUsers, { staleMs: 300000 }).catch(
 			publicReadFailure("home.users"),
 		),
@@ -210,7 +206,7 @@ async function getHotelData() {
 			15_000,
 			() =>
 				db
-					.select({ username: User.username, look: User.look })
+					.select({ id: User.id, username: User.username, look: User.look })
 					.from(User)
 					.where(eq(User.online, "1"))
 					.limit(12),
@@ -259,11 +255,22 @@ export default async function Home() {
 		totalPhotos,
 		articleCount,
 		articles,
-		recentUsers,
+		recentUsers: rawRecentUsers,
 		recentPhotos,
 		logo,
 	} = await getHotelData();
 
+	// Users who hide their online state must not surface in the "who is online"
+	// rails on the homepage either.
+	const recentUserPrivacy = await loadProfilePrivacyMap(
+		(rawRecentUsers ?? []).map((u) => u.id),
+	);
+	const recentUsers =
+		rawRecentUsers === null
+			? null
+			: rawRecentUsers.filter(
+					(u) => recentUserPrivacy.get(u.id)?.online !== false,
+				);
 	const captcha = await captchaConfig();
 	const nonce = (await headers()).get("x-nonce") ?? undefined;