feat(admin): 商品编辑页增加上一个/下一个导航

Co-Authored-By: Devin AI <158243242+devin-ai-integration[bot]@users.noreply.github.com>

admin-frontend/src/App.tsx

@@ -28,6 +28,7 @@ export default function App() {
   const [tab, setTab] = useState<Tab>("products");
   const [pending, setPending] = useState<number | null>(null);
   const [view, setView] = useState<View>({ name: "list" });
+  const [navIds, setNavIds] = useState<string[]>([]);
 
   useEffect(() => {
     if (!authed) return;
@@ -190,9 +191,19 @@ export default function App() {
         ) : tab === "submissions" ? (
           <SubmissionsPage onPending={setPending} />
         ) : view.name === "list" ? (
-          <ProductList onOpen={(id) => setView({ name: "detail", id })} />
+          <ProductList
+            onOpen={(id, ids) => {
+              setNavIds(ids);
+              setView({ name: "detail", id });
+            }}
+          />
         ) : (
-          <ProductDetail id={view.id} onBack={() => setView({ name: "list" })} />
+          <ProductDetail
+            id={view.id}
+            ids={navIds}
+            onNavigate={(id) => setView({ name: "detail", id })}
+            onBack={() => setView({ name: "list" })}
+          />
         )}
       </main>
     </div>