feat: 细化差旅票据费用明细分类并自动计算出差补贴

将差旅费用明细拆分为火车票、机票、住宿票、乘车等细分类
型，根据票据字段自动生成行程/事由描述，结合规则引擎自
动计算出差补贴金额，前端适配费用明细编辑和差旅票据审
核交互，补充单元测试覆盖。

web/tests/requestProgressSteps.test.mjs

@@ -98,6 +98,71 @@ test('progress steps do not expose approver email when manager name is available
   }
 })
 
+test('travel expense items describe departure return and lodging time below the date', () => {
+  const request = mapExpenseClaimToRequest({
+    id: 'claim-travel-time-labels',
+    claim_no: 'EXP-202605-TRAVEL',
+    employee_name: '张三',
+    department_name: '市场部',
+    expense_type: 'travel',
+    reason: '北京客户现场出差',
+    location: '北京',
+    amount: 1108,
+    invoice_count: 3,
+    occurred_at: '2026-05-13T01:00:00.000Z',
+    created_at: '2026-05-13T01:30:00.000Z',
+    updated_at: '2026-05-13T03:30:00.000Z',
+    status: 'draft',
+    approval_stage: '待提交',
+    risk_flags_json: [],
+    items: [
+      {
+        id: 'outbound-train',
+        item_type: 'train_ticket',
+        item_reason: '从广州南到北京南',
+        item_location: '北京',
+        item_date: '2026-05-13',
+        item_amount: 354,
+        invoice_id: 'outbound.png'
+      },
+      {
+        id: 'hotel',
+        item_type: 'hotel_ticket',
+        item_reason: '北京全季酒店',
+        item_location: '北京',
+        item_date: '2026-05-14',
+        item_amount: 100,
+        invoice_id: 'hotel.png'
+      },
+      {
+        id: 'return-train',
+        item_type: 'train_ticket',
+        item_reason: '从北京南到广州南',
+        item_location: '广州',
+        item_date: '2026-05-15',
+        item_amount: 354,
+        invoice_id: 'return.png'
+      },
+      {
+        id: 'allowance',
+        item_type: 'travel_allowance',
+        item_reason: '系统自动计算出差补贴',
+        item_location: '北京',
+        item_date: '2026-05-15',
+        item_amount: 300,
+        invoice_id: '',
+        is_system_generated: true
+      }
+    ]
+  })
+
+  assert.equal(request.expenseItems.find((item) => item.id === 'outbound-train')?.dayLabel, '出发时间')
+  assert.equal(request.expenseItems.find((item) => item.id === 'return-train')?.dayLabel, '返回时间')
+  assert.equal(request.expenseItems.find((item) => item.id === 'hotel')?.dayLabel, '住宿时间')
+  assert.equal(request.expenseItems.at(-1)?.id, 'allowance')
+  assert.equal(request.expenseItems.at(-1)?.dayLabel, '系统自动计算')
+})
+
 test('completed finance approval marks finance and archive progress steps', () => {
   const request = mapExpenseClaimToRequest({
     id: 'claim-finance-completed',