feat: wire superadmin p1 data

frontend/superadmin/src/service/CouponService.js

@@ -0,0 +1,44 @@
+import { requestJson } from './apiClient';
+
+function normalizeItems(items) {
+    if (Array.isArray(items)) return items;
+    if (items && typeof items === 'object') return [items];
+    return [];
+}
+
+export const CouponService = {
+    async listCoupons({ page, limit, id, tenant_id, tenant_code, tenant_name, keyword, type, status, created_at_from, created_at_to, sortField, sortOrder } = {}) {
+        const iso = (d) => {
+            if (!d) return undefined;
+            const date = d instanceof Date ? d : new Date(d);
+            if (Number.isNaN(date.getTime())) return undefined;
+            return date.toISOString();
+        };
+
+        const query = {
+            page,
+            limit,
+            id,
+            tenant_id,
+            tenant_code,
+            tenant_name,
+            keyword,
+            type,
+            status,
+            created_at_from: iso(created_at_from),
+            created_at_to: iso(created_at_to)
+        };
+        if (sortField && sortOrder) {
+            if (sortOrder === 1) query.asc = sortField;
+            if (sortOrder === -1) query.desc = sortField;
+        }
+
+        const data = await requestJson('/super/v1/coupons', { query });
+        return {
+            page: data?.page ?? page ?? 1,
+            limit: data?.limit ?? limit ?? 10,
+            total: data?.total ?? 0,
+            items: normalizeItems(data?.items)
+        };
+    }
+};