템플릿 slug 구조와 빈 DB 초기화를 정리

frontend/src/components/admin/AdminFeaturedSection.vue

@@ -31,7 +31,7 @@ const props = defineProps({
               <span class="featuredCard__rank">{{ index + 1 }}</span>
               <div>
                 <div class="featuredCard__title">{{ template.name }}</div>
-                <div class="featuredCard__id">{{ template.id }}</div>
+                <div class="featuredCard__id">{{ template.slug || template.id }}</div>
               </div>
             </div>
             <div class="featuredCard__actions">
@@ -55,7 +55,7 @@ const props = defineProps({
             @click="props.addFeaturedTemplate(template.id)"
           >
             <span>{{ template.name }}</span>
-            <span class="featuredPickerItem__id">{{ template.id }}</span>
+            <span class="featuredPickerItem__id">{{ template.slug || template.id }}</span>
           </button>
         </div>
       </div>