fix: Center Request Vehicle button and translate maker/model names

- Adjust layout to center Request Vehicle with PromoPreference on right
- Use translateCarName for maker/model names in combo boxes

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

frontend/src/app/page.tsx

@@ -47,8 +47,11 @@ export default function Home() {
         <FilmStripSlider banners={banners} settings={bannerSettings} />
 
         <div className="container mx-auto px-4 py-4 sm:py-8">
-          <div className="flex flex-col lg:flex-row items-center justify-center gap-4 lg:gap-8">
-            {/* Request Vehicle Button */}
+          <div className="flex flex-col lg:flex-row items-center gap-4 lg:gap-6">
+            {/* Spacer for centering Request Vehicle */}
+            <div className="hidden lg:block lg:flex-1"></div>
+
+            {/* Request Vehicle Button - Centered */}
             <Link
               href="/vehicle-request"
               className="inline-block bg-yellow-500 text-white font-semibold px-6 py-2.5 sm:px-8 sm:py-3 rounded-lg hover:bg-yellow-600 transition shadow-lg text-sm sm:text-base"
@@ -57,11 +60,13 @@ export default function Home() {
             </Link>
 
             {/* Divider */}
-            <div className="hidden lg:block w-px h-24 bg-white/30"></div>
+            <div className="hidden lg:block w-px h-16 bg-white/30"></div>
             <div className="lg:hidden w-32 h-px bg-white/30"></div>
 
-            {/* Promo Preference */}
-            <PromoPreference />
+            {/* Promo Preference - Right side */}
+            <div className="lg:flex-1 flex justify-center lg:justify-start">
+              <PromoPreference />
+            </div>
           </div>
         </div>
       </section>