feat(server): 报销单输出工号/邮箱并扩展申请人邮箱前缀匹配

- ExpenseClaimRead 新增 employee_no/employee_email 字段，ExpenseClaim 模型补对应只读属性
- expense_claim_access_policy 在姓名匹配未果时，按 candidate@% 邮箱前缀匹配 Employee.email，命中唯一记录即返回
- test_backend_pagination/test_expense_claim_service 补充工号/邮箱字段断言与邮箱前缀匹配用例
- 更新公司通信费报销规则表

server/src/app/services/expense_claim_access_policy.py

@@ -509,6 +509,20 @@ class ExpenseClaimAccessPolicy:
             if employee is not None:
                 return employee
 
+        for candidate in normalized_candidates:
+            if self.is_email_like(candidate):
+                continue
+            matches = list(
+                self.db.scalars(
+                    select(Employee)
+                    .options(*load_options)
+                    .where(func.lower(Employee.email).like(f"{candidate.lower()}@%"))
+                    .limit(2)
+                ).all()
+            )
+            if len(matches) == 1:
+                return matches[0]
+
         for candidate in normalized_candidates:
             matches = list(
                 self.db.scalars(