feat(downloading): add NoDataFound component for empty downloaders

Add the NoDataFound component to the downloading page to display a 404 error message when there are no enabled downloaders. This component will show an error code, title, and description to guide users on how to configure and enable downloaders in the settings.

Closes #197

src/pages/downloading.vue

@@ -3,6 +3,7 @@ import api from '@/api'
 import { DownloaderConf } from '@/api/types'
 import DownloadingListView from '@/views/reorganize/DownloadingListView.vue'
 import router from '@/router'
+import NoDataFound from '@/components/NoDataFound.vue'
 
 const route = useRoute()
 const activeTab = ref(route.query.tab)
@@ -36,7 +37,7 @@ onMounted(() => {
 </script>
 
 <template>
-  <div>
+  <div v-if="enabledDownloaders.length > 0">
     <VTabs v-model="activeTab">
       <VTab v-for="item in enabledDownloaders" :value="item.name" @to="jumpTab(item.name)">
         <span class="mx-5">{{ item.name }}</span>
@@ -51,4 +52,10 @@ onMounted(() => {
       </VWindowItem>
     </VWindow>
   </div>
+  <NoDataFound
+    v-else
+    error-code="404"
+    error-title="没有下载器"
+    error-description="请先在设置中正确配置并启用下载器。"
+  />
 </template>