Registro + activación por email en Next.js (SRP6 + nodemailer)

- lib/mail.ts: transporte SMTP (nodemailer, mismas creds Gmail que Django).
- lib/register.ts: registerAccount (valida, comprueba email existente, crea fila en
  home_accountactivation reutilizando la tabla de Django, envía email de activación);
  activateAccount (crea battlenet_accounts con SRP6 v2 + account con SRP6 Grunt, como
  activate_account_view: expansion=2, battlenet_index=1; borra la activación).
- Route handlers /api/auth/register y /api/auth/activate.
- Páginas app/[locale]/register (RegisterForm cliente) y app/[locale]/activate-account
  (ActivateClient auto-POST al abrir el enlace). Textos en messages (Register, Activate).

Validado: validaciones (missingFields/passwordMismatch/invalidEmail/passwordTooLong);
ciclo completo activación->crea bnet+account->login OK con la cuenta creada
(needsSelection=false), password mala->invalidCredentials. Todo en TS, crypto validada.

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

web-next/messages/en.json

@@ -44,5 +44,32 @@
     "noAccounts": "No game accounts were found linked to this Battle.net account.",
     "entering": "Entering…",
     "error": "The account could not be selected."
+  },
+  "Register": {
+    "title": "Create account",
+    "info": "Your account is Battle.net type: it is identified by your email. The password must be alphanumeric and up to 16 characters. The email must be a Gmail address.",
+    "password": "Password",
+    "confPassword": "Confirm password",
+    "email": "Gmail email address",
+    "confEmail": "Confirm email address",
+    "recruiter": "Recruiter (optional)",
+    "terms": "I accept the Rules, Terms and Conditions and Privacy Policy",
+    "submit": "Create account",
+    "creating": "Creating…",
+    "success": "The account has been created. Check your email to activate it.",
+    "missingFields": "Please fill in all fields.",
+    "passwordMismatch": "Passwords do not match.",
+    "passwordTooLong": "The password must not exceed 16 characters.",
+    "invalidEmail": "The email address is not valid.",
+    "emailExists": "An account with that email already exists.",
+    "recruiterNotFound": "The recruiter entered does not exist.",
+    "genericError": "Something went wrong. Please try again later."
+  },
+  "Activate": {
+    "activating": "Activating your account…",
+    "success": "Account activated! You can now sign in.",
+    "invalidLink": "The link is invalid or has already been used.",
+    "expiredLink": "The link has expired. Please request a new one.",
+    "goLogin": "Go to sign in"
   }
 }