项目管理界面显示异常优化

frontend/src/views/admin/ProjectMembers.vue

@@ -30,7 +30,9 @@
             </el-tag>
           </template>
         </el-table-column>
-        <el-table-column prop="added_at" label="加入时间" width="200" />
+        <el-table-column prop="added_at" label="加入时间" width="200">
+          <template #default="scope">{{ displayDateTime(scope.row.added_at) }}</template>
+        </el-table-column>
         <el-table-column label="操作" width="360" fixed="right">
           <template #default="scope">
             <el-select
@@ -104,6 +106,7 @@ import type { Study, StudyMember, UserInfo } from "../../types/api";
 import { useAuthStore } from "../../store/auth";
 import { evaluateAction } from "../../guards/actionGuard";
 import { logAudit } from "../../audit";
+import { displayDateTime } from "../../utils/display";
 
 const route = useRoute();
 const projectId = computed(() => route.params.projectId as string);