feat: 添加模板为空时的提示信息

pages/generation/ppt-templates.vue

@@ -56,6 +56,7 @@ const onDownloadClick = (ppt: PPTTemplate) => {
       <!-- cat selector -->
       <div class="flex flex-wrap gap-2">
         <div
+          v-if="pptTemplates?.data.items.length !== 0"
           v-for="cat in [
             { id: 0, type: '全部' },
             ...(pptCategories?.data.items || []),
@@ -74,6 +75,19 @@ const onDownloadClick = (ppt: PPTTemplate) => {
 
       <div class="space-y-4">
         <div
+          v-if="pptTemplates?.data.items.length === 0"
+          class="w-full py-20 flex flex-col justify-center items-center gap-2"
+        >
+          <Icon
+            class="text-7xl text-neutral-300 dark:text-neutral-700"
+            name="i-tabler-photo-hexagon"
+          />
+          <p class="text-sm text-neutral-500 dark:text-neutral-400">
+            暂时没有可用模板
+          </p>
+        </div>
+        <div
+          v-else
           class="grid grid-cols-1 md:grid-cols-2 lg:grid-cols-3 2xl:grid-cols-4 gap-4 mt-4"
         >
           <div