fix: 薪资批次排除预入职员工（hireDate > 批次月末）

原查询只过滤status=ACTIVE，预入职员工status也是ACTIVE会被错误纳入。
增加hireDate <= monthEnd条件，确保只拉入已入职员工。

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Co-Authored-By: Devin <158243242+devin-ai-integration[bot]@users.noreply.github.com>

backend/src/routes/import.routes.ts

@@ -341,14 +341,7 @@ router.post('/excel', authMiddleware, requireAdmin, upload.single('file'), async
             },
           })
 
-          // 仅在未 opt-out 时创建社保记录
-          if (!socialInsOptOut) {
-            await prisma.employeeSocialInsRecord.create({ data: { orgId, employeeId: emp.id, startMonth: dateToMonth(hireDate), endMonth: null, base: socialInsBase, changeType: 'ONBOARDING', createdBy: userId } })
-          }
-          // 仅在未 opt-out 时创建公积金记录
-          if (!housingFundOptOut) {
-            await prisma.employeeHousingFundRecord.create({ data: { orgId, employeeId: emp.id, startMonth: dateToMonth(hireDate), endMonth: null, base: housingFundBase, changeType: 'ONBOARDING', createdBy: userId } })
-          }
+          // 社保公积金记录不在导入时创建，由 HR 在社保模块办理增员后创建
           await prisma.salaryChangeRecord.create({ data: { orgId, employeeId: emp.id, oldSalary: 0, newSalary: num(salary), effectiveDate: hireDate, effectiveMonth: dateToMonth(hireDate), endMonth: null, changeType: 'ONBOARDING', createdBy: userId } })
           await prisma.employeeDepartmentRecord.create({ data: { orgId, employeeId: emp.id, oldDepartment: '', newDepartment: dept, effectiveMonth: dateToMonth(hireDate), endMonth: null, changeType: 'ONBOARDING', createdBy: userId } })