Use site language for emails

src/App.vue

@@ -907,11 +907,17 @@ function setLang(lang) {
   // (risk banner, recs, budget, timeline) so they pick up the new language
   // without a reload.
   if (document.body.classList.contains('results-active')) rerenderResults()
+  syncPreferredLanguageField()
   saveState()
 }
 
 function t(key) { return T[currentLang][key] || T['en'][key] || key }
 
+function syncPreferredLanguageField() {
+  const field = document.getElementById('f_pref_lang')
+  if (field) field.value = currentLang
+}
+
 // ══════════════════════════════════════
 // QUESTIONS
 // ══════════════════════════════════════
@@ -1691,7 +1697,7 @@ function submitCapture(e) {
   const city       = g('f_city')
   const country    = g('f_country')
   const phone      = g('f_phone')
-  const prefLang   = g('f_pref_lang') || currentLang
+  const prefLang   = currentLang
   const protein    = g('f_protein_detail')
   const newsletter = gc('f_newsletter') ? 'yes' : 'no'
 
@@ -2121,6 +2127,7 @@ let savedScrollY = 0
 function openCaptureModal() {
   const modal = document.getElementById('capture-modal')
   if (!modal) return
+  syncPreferredLanguageField()
   savedScrollY = window.scrollY || window.pageYOffset || 0
   modal.classList.add('open')
   modal.setAttribute('aria-hidden', 'false')