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/RequestsView.js

@@ -1,5 +1,6 @@
 import { computed, ref, watch } from 'vue'
 
+import EnterpriseSelect from '../../components/shared/EnterpriseSelect.vue'
 import TableLoadingState from '../../components/shared/TableLoadingState.vue'
 import TableEmptyState from '../../components/shared/TableEmptyState.vue'
 import { normalizeRequestForUi } from '../../utils/requestViewModel.js'
@@ -12,6 +13,7 @@ function extractRowDate(value) {
 export default {
   name: 'RequestsView',
   components: {
+    EnterpriseSelect,
     TableLoadingState,
     TableEmptyState
   },
@@ -61,11 +63,10 @@ export default {
     const currentPage = ref(1)
     const pageSize = ref(10)
     const pageSizes = [10, 20, 50]
-    const pageSizeOpen = ref(false)
+    const pageSizeOptions = pageSizes.map((size) => ({ label: `${size} 条/页`, value: size }))
 
     function changePageSize(size) {
       pageSize.value = size
-      pageSizeOpen.value = false
       currentPage.value = 1
     }
 
@@ -132,7 +133,7 @@ export default {
           icon: 'mdi mdi-receipt-text-plus-outline',
           actionLabel: '',
           actionIcon: '',
-          tone: 'emerald',
+          tone: 'theme',
           artLabel: 'CLAIM',
           tips: ['保存草稿后会自动回到这里', '支持草稿、待提交、审批中和已完成全流程管理']
         }
@@ -163,7 +164,6 @@ export default {
       rangeEnd.value = ''
       appliedStart.value = ''
       appliedEnd.value = ''
-      pageSizeOpen.value = false
       currentPage.value = 1
     }
 
@@ -197,7 +197,7 @@ export default {
       currentPage,
       pageSize,
       pageSizes,
-      pageSizeOpen,
+      pageSizeOptions,
       changePageSize,
       filteredRows,
       totalCount,