fix: resolve response format mismatches causing data loading failures in Dashboard, ImBots, Promotion, Knowledge pages

frontend/src/pages/admin/Promotion.tsx

@@ -102,7 +102,7 @@ const Promotion: React.FC = () => {
   const loadStats = useCallback(async () => {
     try {
       const res = await adminAPI.getPromotionStats();
-      if (res.success) {
+      if (res.data) {
         setStats(res.data);
       }
     } catch (err: any) {
@@ -115,7 +115,7 @@ const Promotion: React.FC = () => {
     setLoading(true);
     try {
       const res = await adminAPI.getPromotions({ page, page_size: 20 });
-      if (res.success) {
+      if (res.data) {
         setPromotions(res.data.items);
         setTotalPromos(res.data.total);
         setPromoPage(page);
@@ -132,7 +132,7 @@ const Promotion: React.FC = () => {
     setLoading(true);
     try {
       const res = await adminAPI.getReferralLinks({ page, page_size: 20 });
-      if (res.success) {
+      if (res.data) {
         setReferralLinks(res.data.items);
         setTotalLinks(res.data.total);
         setLinkPage(page);
@@ -149,7 +149,7 @@ const Promotion: React.FC = () => {
     setLoading(true);
     try {
       const res = await adminAPI.getReferralRewards({ page, page_size: 20 });
-      if (res.success) {
+      if (res.data) {
         setRewards(res.data.items);
         setTotalRewards(res.data.total);
         setRewardPage(page);
@@ -165,8 +165,8 @@ const Promotion: React.FC = () => {
   const loadLeaderboard = useCallback(async () => {
     try {
       const res = await adminAPI.getPromotionLeaderboard({ limit: 50 });
-      if (res.success) {
-        setLeaderboard(res.data.leaderboard);
+      if (res.data) {
+        setLeaderboard(res.data.items || res.data.leaderboard || []);
       }
     } catch (err: any) {
       console.error('Failed to load leaderboard:', err);
@@ -813,7 +813,7 @@ const LinkModal: React.FC<LinkModalProps> = ({ onSave, onCancel }) => {
   useEffect(() => {
     adminAPI.getPromotions({ status: 'active', page: 1, page_size: 100 })
       .then(res => {
-        if (res.success) setPromotions(res.data.items);
+        if (res.data) setPromotions(res.data.items);
       })
       .catch(err => console.error('Failed to load active promotions:', err));
   }, []);