feat(antispam): add server-side contact form spam guard (honeypot, time-trap, rate limit, link cap)

components/ContactForm.tsx

@@ -12,6 +12,7 @@ export default function ContactForm() {
   const { trackEvent } = useAnalytics();
   const [status, setStatus] = useState<'idle' | 'submitting' | 'success' | 'error'>('idle');
   const [hasStarted, setHasStarted] = useState(false);
+  const [formLoadedAt] = useState(() => Date.now());
 
   const handleFocus = (fieldId: string) => {
     // Initial form start
@@ -152,6 +153,8 @@ export default function ContactForm() {
           style={{ display: 'none' }}
           aria-hidden="true"
         />
+        {/* Anti-spam time-trap: server rejects submissions faster than a human could fill the form */}
+        <input type="hidden" name="form_loaded_at" value={formLoadedAt} />
         <div className="space-y-1 md:space-y-2">
           <Label htmlFor="contact-name">{t('form.name')}</Label>
           <Input