Localize account holder auth page

- Replace hardcoded Korean text with translation keys
- Update header title to use t('additionalService.accountHolderAuth.title')
- Localize filter and download button labels
- Localize sort options (latest/oldest)
- All translation keys already exist in ko.json and en.json

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

src/pages/additional-service/account-holder-auth/account-holder-auth-page.tsx

@@ -47,7 +47,7 @@ export const AccountHolderAuthPage = () => {
   const [toDate, setToDate] = useState(moment().format('YYYYMMDD'));
   const [authStatus, setAuthStatus] = useState<AccountHolderAuthStatus>(AccountHolderAuthStatus.ALL)
   const [emailBottomSheetOn, setEmailBottomSheetOn] = useState<boolean>(false);
-  useSetHeaderTitle('계좌점유인증');
+  useSetHeaderTitle(t('additionalService.accountHolderAuth.title'));
   useSetHeaderType(HeaderType.LeftArrow);
   useSetFooterMode(false);
   useSetOnBack(() => {
@@ -184,23 +184,23 @@ export const AccountHolderAuthPage = () => {
                   />
                   <button
                     className="filter-btn"
-                    aria-label="필터"
+                    aria-label={t('common.filter')}
                   >
                     <img
                       src={IMAGE_ROOT + '/ico_setting.svg'}
-                      alt="검색옵션"
+                      alt={t('common.searchOptions')}
                       onClick={() => onClickToOpenFilter()}
                     />
                   </button>
                 </div>
                 <button
                   className="download-btn"
-                  aria-label="다운로드"
+                  aria-label={t('common.download')}
                   onClick={() => onClickToOpenEmailBottomSheet()}
                 >
                   <img
                     src={IMAGE_ROOT + '/ico_download.svg'}
-                    alt="다운로드"
+                    alt={t('common.download')}
                   />
                 </button>
               </div>
@@ -211,8 +211,8 @@ export const AccountHolderAuthPage = () => {
                 sortType={sortType}
                 onClickToSort={onClickToSort}
                 sortOptions={[
-                  { key: SortTypeKeys.LATEST, label: '최신순' },
-                  { key: SortTypeKeys.OLDEST, label: '오래된순' }
+                  { key: SortTypeKeys.LATEST, label: t('common.latest') },
+                  { key: SortTypeKeys.OLDEST, label: t('common.oldest') }
                 ]}
               ></SortTypeBox>
               <div className="excrow">