fix(frontend): language switcher cursor and persistence logic

frontend/src/components/language-switcher.tsx

@@ -34,7 +34,7 @@ export function LanguageSwitcher() {
                     <DropdownMenuItem
                         key={l.code}
                         onClick={() => setLocale(l.code)}
-                        className="flex items-center gap-2"
+                        className="flex items-center gap-2 cursor-pointer"
                     >
                         <span className="text-lg">{l.flag}</span>
                         <span>{l.name}</span>

frontend/src/lib/i18n.tsx

@@ -66,6 +66,17 @@ export function I18nProvider({ children }: { children: ReactNode }) {
         return value;
     }, [locale]);
 
+    // Sync from localStorage on mount to handle hydration mismatch or initial load
+    useEffect(() => {
+        if (typeof window !== 'undefined') {
+            const stored = localStorage.getItem(localeStorageKey);
+            if (stored && stored in dictionaries && stored !== locale) {
+                console.log('[I18n] Restoring locale from storage:', stored);
+                setLocale(stored as Locale);
+            }
+        }
+    }, []);
+
     useEffect(() => {
         if (typeof window === 'undefined') return;
         localStorage.setItem(localeStorageKey, locale);