style: 全局 UI 主题皮肤重构与样式模块化

引入 Element Plus 主题定制和主题皮肤 composable，将全局
样式拆分为组件级独立 CSS 文件（侧边栏、顶栏、工作台等），
统一色彩变量和间距规范，重构所有视图和组件样式以适配新
主题系统，优化图表和知识图谱组件视觉表现，提取审计和差
旅报销相关子组件。

web/src/views/scripts/TravelRequestDetailView.js

@@ -2,8 +2,11 @@ import { computed, onBeforeUnmount, reactive, ref, watch } from 'vue'
 
 import { useSystemState } from '../../composables/useSystemState.js'
 import { useToast } from '../../composables/useToast.js'
+import EnterpriseSelect from '../../components/shared/EnterpriseSelect.vue'
 import ConfirmDialog from '../../components/shared/ConfirmDialog.vue'
-import ReturnReasonDialog from '../../components/shared/ReturnReasonDialog.vue'
+import TravelRequestApprovalDialog from '../../components/travel/TravelRequestApprovalDialog.vue'
+import TravelRequestDeleteDialog from '../../components/travel/TravelRequestDeleteDialog.vue'
+import TravelRequestReturnDialog from '../../components/travel/TravelRequestReturnDialog.vue'
 import {
   approveExpenseClaim,
   createExpenseClaimItem,
@@ -358,7 +361,10 @@ export default {
   name: 'TravelRequestDetailView',
   components: {
     ConfirmDialog,
-    ReturnReasonDialog
+    EnterpriseSelect,
+    TravelRequestApprovalDialog,
+    TravelRequestDeleteDialog,
+    TravelRequestReturnDialog
   },
   props: {
     request: {