Hide decorative flags from screen readers in the language selector

The flags had titles that repeated the button text. Also mark each
language name with its own lang so it's pronounced correctly.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

src/components/ui/languageSelector.tsx

@@ -24,13 +24,13 @@ const LanguageSelector = () => {
     <div className={styles.languageSwitcher}>
       {locale === "no" ? (
         <button onClick={() => changeLocale("en")} className={styles.button}>
-          <GB className={styles.flag} title="English flag" />
-          English
+          <GB className={styles.flag} aria-hidden="true" />
+          <span lang="en">English</span>
         </button>
       ) : (
         <button onClick={() => changeLocale("no")} className={styles.button}>
-          <NO className={styles.flag} title="Norwegian flag" />
-          Norsk
+          <NO className={styles.flag} aria-hidden="true" />
+          <span lang="no">Norsk</span>
         </button>
       )}
     </div>