Cierra el flujo de login: logout, selector de cuenta y /account con guardas

- Route handlers: /api/auth/logout (destroy sesión), /api/auth/select-account
  (fija la cuenta de juego elegida, valida que pertenece a la bnet en sesión).
- app/[locale]/select-account: página SSR (guarda: sin bnetId -> login) + lista de
  cuentas de juego (SelectAccountForm cliente) -> /account.
- app/[locale]/account: página protegida (sin bnetId -> login; sin username ->
  select-account) con datos de sesión + LogoutButton.
- Textos en messages (Account, SelectAccount).

Verificado: guardas locale-aware (ES /account -> /login, EN /en/account -> /en/login,
307), logout OK, select-account sin sesión 401. Redirect i18n con next-intl.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

web-next/app/[locale]/account/LogoutButton.tsx

@@ -0,0 +1,28 @@
+'use client'
+
+import { useState } from 'react'
+import { useTranslations } from 'next-intl'
+import { useRouter } from '@/i18n/navigation'
+
+export function LogoutButton() {
+  const t = useTranslations('Account')
+  const router = useRouter()
+  const [busy, setBusy] = useState(false)
+
+  async function logout() {
+    setBusy(true)
+    await fetch('/api/auth/logout', { method: 'POST', credentials: 'same-origin' })
+    router.push('/')
+    router.refresh()
+  }
+
+  return (
+    <button
+      onClick={logout}
+      disabled={busy}
+      className="rounded border border-amber-900/60 px-4 py-2 text-amber-200 disabled:opacity-60"
+    >
+      {t('logout')}
+    </button>
+  )
+}

web-next/app/[locale]/account/page.tsx

@@ -0,0 +1,33 @@
+import { getTranslations, setRequestLocale } from 'next-intl/server'
+import { redirect } from '@/i18n/navigation'
+import { getSession } from '@/lib/session'
+import { LogoutButton } from './LogoutButton'
+
+export const dynamic = 'force-dynamic'
+
+export default async function AccountPage({ params }: { params: Promise<{ locale: string }> }) {
+  const { locale } = await params
+  setRequestLocale(locale)
+  const t = await getTranslations('Account')
+
+  const session = await getSession()
+  if (!session.bnetId) redirect({ href: '/login', locale })
+  if (!session.username) redirect({ href: '/select-account', locale })
+
+  return (
+    <main className="mx-auto max-w-2xl px-4 py-8">
+      <h1 className="mb-6 text-2xl font-bold text-amber-500">{t('title')}</h1>
+      <div className="space-y-2 rounded-lg border border-amber-900/60 bg-[#241812] p-4 text-sm">
+        <p>
+          {t('bnetAccount')}: <span className="text-amber-400">{session.bnetEmail}</span>
+        </p>
+        <p>
+          {t('gameAccount')}: <span className="text-amber-400">{session.username}</span>
+        </p>
+      </div>
+      <div className="mt-6">
+        <LogoutButton />
+      </div>
+    </main>
+  )
+}