Double desktop header logo, add English caption under each carousel title

- Header logo (desktop variant) doubled: 40/48px -> 80/96px.
- Each dynamic store-specials carousel now shows an English caption
  under its title at 50% opacity, derived from the group's real `key`
  (e.g. "top-selling" -> "TOP SELLING") rather than inventing a
  translation of the Persian title, which the API doesn't provide.
  New SectionTitle `enSubtitle` prop (separate from the existing
  inline `enTitle`) carries this.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

src/components/ui/SectionTitle.tsx

@@ -1,12 +1,22 @@
 type SectionTitleProps = {
   title: string;
   enTitle?: string;
+  // Shown on its own line under the title (not inline like enTitle), at 50%
+  // opacity — used for the homepage's dynamic store-specials carousels.
+  enSubtitle?: string;
   subtitle?: string;
   action?: string;
   actionHref?: string;
 };
 
-export function SectionTitle({ title, enTitle, subtitle, action, actionHref }: SectionTitleProps) {
+export function SectionTitle({
+  title,
+  enTitle,
+  enSubtitle,
+  subtitle,
+  action,
+  actionHref,
+}: SectionTitleProps) {
   return (
     <div className="mb-6 flex items-end justify-between gap-4">
       <div>
@@ -22,6 +32,15 @@ export function SectionTitle({ title, enTitle, subtitle, action, actionHref }: S
             </span>
           )}
         </div>
+        {enSubtitle && (
+          <p
+            className="font-display mt-1 text-xs font-semibold tracking-wide text-foreground uppercase opacity-50 md:text-sm"
+            lang="en"
+            dir="ltr"
+          >
+            {enSubtitle}
+          </p>
+        )}
         {subtitle && (
           <p className="mt-1 text-sm text-muted">{subtitle}</p>
         )}