refactor(frontend): 重构前端样式体系，统一资源路径与代码规范

1.  重构SCSS样式结构，将原有分散的样式文件整合到custom目录下，统一使用@use替代@import
2.  删除冗余的全局样式文件，将样式逻辑内联到对应组件或集中到core目录
3.  新增DOMPurify依赖，对富文本内容添加XSS防护
4.  修复metrics端点暴露的兼容性问题，优化启动banner样式
5.  移除无用的权限校验代码，重构工作流组件路径与命名
6.  优化样式混合宏与响应式布局，修复部分组件样式冲突

frontend/web/src/views/fastlink/article/components/ArticleDetailDrawer.vue

@@ -25,9 +25,7 @@
           留言讨论
         </ElButton>
         <ElButton @click="visible = false">关闭</ElButton>
-        <ElButton v-if="articleId != null" v-auth="'edit'" type="primary" @click="onEditClick">
-          编辑
-        </ElButton>
+        <ElButton v-if="articleId != null" type="primary" @click="onEditClick"> 编辑 </ElButton>
       </div>
     </template>
   </ElDrawer>
@@ -37,6 +35,7 @@
 import "@styles/core/md.scss";
 import "@styles/custom/one-dark-pro.scss";
 import axios from "axios";
+import DOMPurify from "dompurify";
 
 defineOptions({ name: "ArticleDetailDrawer" });
 
@@ -91,7 +90,7 @@ const fetchDetail = async () => {
 
     if (data.code === 200) {
       articleTitle.value = data.data.title;
-      articleHtml.value = data.data.html_content;
+      articleHtml.value = DOMPurify.sanitize(data.data.html_content);
     } else {
       error.value = "文章加载失败";
     }

frontend/web/src/views/fastlink/article/index.vue

@@ -27,7 +27,7 @@
           <FaSvgIcon icon="ri:message-3-line" class="mr-1" />
           留言墙
         </ElButton>
-        <ElButton type="primary" @click="toAddArticle" v-auth="'add'">新增文章</ElButton>
+        <ElButton type="primary" @click="toAddArticle">新增文章</ElButton>
       </ElCol>
     </ElRow>
 
@@ -65,7 +65,6 @@
               </div>
               <ElButton
                 class="opacity-0 group-hover:opacity-100"
-                v-auth="'edit'"
                 size="small"
                 @click.stop="toEdit(item)"
               >