feat: 重构报销单服务并完善前端提交与审核交互

重构 expense_claims 服务模块结构并优化差旅票据审核逻辑，
增强用户代理服务的票据类型识别，前端报销创建页面拆分为
附件模型和会话模型模块，重构提交编排器和草稿关联确认流
程，更新知识库索引，补充单元测试。

web/tests/attachment-association-confirmation.test.mjs

@@ -0,0 +1,34 @@
+import assert from 'node:assert/strict'
+import test from 'node:test'
+
+import {
+  ATTACHMENT_ASSOCIATION_CONFIRM_HREF,
+  buildAttachmentAssociationConfirmationMessage
+} from '../src/views/scripts/travelReimbursementAttachmentModel.js'
+
+test('attachment association prompt prints recognized receipt details before confirmation link', () => {
+  const message = buildAttachmentAssociationConfirmationMessage({
+    claimNo: 'EXP-202605-001',
+    fileNames: ['train-ticket.pdf'],
+    ocrDocuments: [
+      {
+        filename: 'train-ticket.pdf',
+        document_type: 'train_ticket',
+        scene_label: '差旅票据',
+        summary: '铁路电子客票 武汉-上海 票价 354 元',
+        document_fields: [
+          { key: 'route', label: '行程', value: '武汉-上海' },
+          { key: 'amount', label: '票价', value: '354.00' },
+          { key: 'date', label: '乘车日期', value: '2026-02-20' }
+        ]
+      }
+    ]
+  })
+
+  assert.match(message, /已识别附件信息：/)
+  assert.match(message, /附件类型：差旅票据/)
+  assert.match(message, /行程：武汉-上海/)
+  assert.match(message, /票价：354.00/)
+  assert.match(message, /草稿单号：EXP-202605-001/)
+  assert.match(message, new RegExp(`\\[确认\\]\\(${ATTACHMENT_ASSOCIATION_CONFIRM_HREF}\\)`))
+})