fix(i18n): 繁中開屏 consent 文案不生效 - 寫死繁中文案、清理腳本、文件

- splash: 繁中 consent 使用元件內 ZH_TW_CONSENT，避免 bundle 快取
- splash: 使用 isTraditionalChineseLocaleTag 判斷繁中
- i18n: 註解與 __DEV__ debug log
- package: clean:cache, start:clean, ios:clean, clean:ios-build
- ALL_COPY: 故障排除與 consent 只改 zh-TW.json 說明
- spec_kit: Splash Consent overflow 記錄排查結論

Co-authored-by: Cursor <cursoragent@cursor.com>

client/app/(splash)/splash.tsx

@@ -8,6 +8,7 @@ import { setConsentAccepted, getConsentAccepted } from '../../src/storage/appSto
 import { fetchLegalLinks } from '@/src/services/legalApi';
 import { getOnboardingCompleted } from '@/src/storage/appStorage';
 import { API_BASE_URL } from '@/src/constants/env';
+import { isTraditionalChineseLocaleTag } from '@/src/i18n/locale';
 
 // 导入 SVG 组件
 import FlowersBg from '../../assets/images/index/flowers_endbg.svg';
@@ -15,10 +16,30 @@ import WelcomeBtn from '../../assets/images/index/welcome_btn.svg';
 
 const { width, height } = Dimensions.get('window');
 
+// 繁中開屏 consent 文案：寫死在元件內，避免 Metro/iOS bundle 快取導致永遠顯示舊文案。
+// 若需修改，請改這裡並同步 client/src/i18n/locales/zh-TW.json 的 consent 區塊。
+const ZH_TW_CONSENT = {
+  title: '我們知道，',
+  subtitle: '當媽媽很不容易。',
+  subtitleSecondary: '這裡給你一些溫柔的肯定與提醒',
+};
+
 export default function SplashScreen() {
   const router = useRouter();
-  const { t } = useTranslation();
+  const { t, i18n } = useTranslation();
   const [showConsent, setShowConsent] = useState(false);
+
+  // 繁中時強制使用上方常數（含 zh-TW / zh-Hant / zh-Hant-TW），其餘用 i18n
+  const isZhTW = isTraditionalChineseLocaleTag(i18n.language || '');
+  const title = isZhTW ? ZH_TW_CONSENT.title : t('consent.title');
+  const subtitle = isZhTW ? ZH_TW_CONSENT.subtitle : t('consent.subtitle');
+  const subtitleSecondary = isZhTW ? ZH_TW_CONSENT.subtitleSecondary : t('consent.subtitleSecondary');
+
+  useEffect(() => {
+    if (typeof __DEV__ !== 'undefined' && __DEV__ && showConsent) {
+      console.log('[i18n consent] language=', i18n.language, 'title=', title, 'subtitle=', subtitle);
+    }
+  }, [showConsent, i18n.language, title, subtitle]);
   const [links, setLinks] = useState<{ privacy?: string; terms?: string }>({});
   const [linksLoading, setLinksLoading] = useState(false);
   const mountedRef = useRef(true);
@@ -126,13 +147,16 @@ export default function SplashScreen() {
         />
       </View>
 
-      {/* 文案内容 */}
+      {/* 文案内容：主標題兩行 + 可選二級標題（字號更小、顏色更淺）；繁中為元件內常數，其餘用 i18n */}
       <View style={[styles.contentContainer, { position: 'absolute', top: contentTop }]}>
         <Text style={styles.titleText}>
-          {t('consent.title')}
+          {title}
           {'\n'}
-          {t('consent.subtitle')}
+          {subtitle}
         </Text>
+        {subtitleSecondary ? (
+          <Text style={styles.consentSubtitleSecondary}>{subtitleSecondary}</Text>
+        ) : null}
       </View>
 
       <SafeAreaView style={styles.bottomContainer} edges={['bottom']}>
@@ -213,6 +237,14 @@ const styles = StyleSheet.create({
     fontWeight: '600',
     fontFamily: Platform.OS === 'ios' ? 'STIX Two Text' : 'serif',
   },
+  consentSubtitleSecondary: {
+    marginTop: 12,
+    fontSize: 16,
+    lineHeight: 22,
+    color: 'rgba(119, 47, 0, 0.6)',
+    textAlign: 'center',
+    fontFamily: Platform.OS === 'ios' ? 'STIX Two Text' : 'serif',
+  },
   bottomContainer: {
     position: 'absolute',
     bottom: 60,