chore: remove prototype files and unused UI assets

Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-openagent)

Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>

src/composables/useNavigation.js

@@ -18,6 +18,14 @@ export const navItems = [
     title: '差旅申请/报销',
     desc: '查看员工差旅报销单据、跟踪进度、发起新申请'
   },
+  {
+    id: 'approval',
+    label: '审批中心',
+    navHint: '待审批单据与批量处理',
+    icon: icons.approval,
+    title: '审批中心',
+    desc: '统一处理待审批单据，聚焦效率、风险与 SLA'
+  },
   {
     id: 'chat',
     label: 'AI助手',
@@ -28,11 +36,11 @@ export const navItems = [
   },
   {
     id: 'policies',
-    label: '政策规则',
-    navHint: '制度与校验规则',
+    label: '知识管理',
+    navHint: '制度、文档与知识图谱',
     icon: icons.file,
-    title: '政策规则中心',
-    desc: '维护差旅、招待、采购和发票校验规则。'
+    title: '财务知识管理中心',
+    desc: '上传制度文档、沉淀财务知识、构建知识图谱，面向员工问答与知识管理'
   },
   {
     id: 'audit',