修复伦理与启动管理的显示问题

frontend/src/views/admin/ProjectDetail.vue

@@ -21,7 +21,7 @@
         <el-descriptions-item label="项目名称">{{ project.name }}</el-descriptions-item>
         <el-descriptions-item label="申办方">{{ project.sponsor || "—" }}</el-descriptions-item>
         <el-descriptions-item label="状态">{{ statusLabel(project.status) }}</el-descriptions-item>
-        <el-descriptions-item label="创建时间">{{ project.created_at || "—" }}</el-descriptions-item>
+        <el-descriptions-item label="创建时间">{{ displayDateTime(project.created_at) }}</el-descriptions-item>
       </el-descriptions>
       <el-skeleton v-else :rows="4" animated />
     </el-card>
@@ -48,6 +48,7 @@ import { fetchStudyDetail } from "../../api/studies";
 import type { Study } from "../../types/api";
 import AttachmentList from "../../components/attachments/AttachmentList.vue";
 import { useStudyStore } from "../../store/study";
+import { displayDateTime } from "../../utils/display";
 
 const route = useRoute();
 const router = useRouter();