create-account: validación en cliente con red-response inmediato

Antes los errores (contraseñas/correos que no coinciden, campos vacíos) solo se
mostraban en rojo tras el envío al servidor. Ahora se validan en el cliente y se
muestran al instante como red-form-response, sin llamada al servidor. Nueva clave
emailMismatch. El servidor sigue haciendo la validación final (Gmail, existe, etc.).

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

web-next/messages/en.json

@@ -170,13 +170,11 @@
   },
   "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.",
@@ -187,7 +185,18 @@
     "emailExists": "An account with that email already exists.",
     "recruiterNotFound": "The recruiter entered does not exist.",
     "genericError": "Something went wrong. Please try again later.",
-    "captchaFailed": "Anti-bot verification failed. Please retry."
+    "captchaFailed": "Anti-bot verification failed. Please retry.",
+    "bnetType": "Your account is a Battle.net account: it is identified by your email address.",
+    "passwordRule": "The password must be alphanumeric and up to 16 characters long.",
+    "emailRule": "The email must be a Gmail address you have access to.",
+    "activation1": "Once the account has been created successfully, an email with an activation link will be sent.",
+    "activation2": "If you do not use the activation link, the account cannot be used to connect to the server.",
+    "loginHint": "When logging in, use your EMAIL address.",
+    "recruiterOptional": "Optional: only if a friend recruited you.",
+    "notUs": "I confirm that I am not accessing this service from the United States.",
+    "termsRich": "I accept the <terms>Terms and Conditions</terms> and the <privacy>Privacy Policy</privacy>.",
+    "showPassword": "Show/hide password",
+    "emailMismatch": "The email addresses do not match."
   },
   "Activate": {
     "activating": "Activating your account…",