feat: 调部门改为调动，使用组织架构部门和职务下拉选择

- 后端：EmployeeDepartmentRecord 增加 oldPosition/newPosition 字段
- 后端：department-change 接口支持 departmentId 关联 + position 职务变动
- 后端：同步更新 Employee.departmentId 和 Employee.position
- 前端：DeptChangeModal 改为从组织架构下拉选择目标部门（树形）和职务
- 前端：选择部门后自动过滤该部门下的职务
- 前端：按钮文案从"调部门"改为"调动"

Generated with [Devin](https://devin.ai)

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

frontend/src/pages/Roster.tsx

@@ -874,8 +874,8 @@ export default function Roster() {
                             )}
                             <button
                               type="button"
-                              title="调部门"
-                              aria-label={`为${e.name}调整部门`}
+                              title="调动"
+                              aria-label={`为${e.name}调动`}
                               className="rounded-md p-1.5 text-gray-500 transition hover:bg-primary/10 hover:text-primary"
                               onClick={(ev) => {
                                 ev.stopPropagation()

frontend/src/pages/roster/modals.tsx

@@ -2,6 +2,7 @@ import { useState, useEffect } from "react"
 import { useQuery } from "@tanstack/react-query"
 import { toast } from "sonner"
 import { rosterApi, socialInsuranceApi, employeeApi } from '../../lib/api-services'
+import api from '../../lib/api'
 import Button from "../../components/ui/Button"
 import { Input, Label, Select } from "../../components/ui/Input"
 import Modal from "../../components/ui/Modal"
@@ -83,23 +84,55 @@ export function DeptChangeModal({ employee, onClose, onSubmit, loading, error }:
 }) {
   const todayStr = new Date().toISOString().slice(0, 10)
   const [form, setForm] = useState({
-    newDepartment: employee.department || '',
+    departmentId: employee.departmentId || '',
+    newPosition: employee.position || '',
     effectiveDate: todayStr,
     reason: '',
   })
 
+  // 拉取组织架构部门和职务列表
+  const { data: departments = [] } = useQuery({
+    queryKey: ['departments'],
+    queryFn: () => api.get('/departments').then(r => r.data),
+  })
+  const { data: positions = [] } = useQuery({
+    queryKey: ['positions'],
+    queryFn: () => api.get('/positions').then(r => r.data),
+  })
+
+  // 构建部门树形下拉选项（带层级缩进）
+  const deptOptions: { id: string; label: string; level: number }[] = []
+  const buildDeptOptions = (items: any[], parentId: string | null, level: number) => {
+    items.filter(d => d.parentId === parentId).sort((a, b) => a.sortOrder - b.sortOrder).forEach(d => {
+      deptOptions.push({ id: d.id, label: d.name, level })
+      buildDeptOptions(items, d.id, level + 1)
+    })
+  }
+  buildDeptOptions(departments, null, 0)
+
+  // 选中新部门后，过滤该部门下的职务（如果职务有 departmentId 关联）
+  const filteredPositions = form.departmentId
+    ? positions.filter((p: any) => !p.departmentId || p.departmentId === form.departmentId)
+    : positions
+
+  const selectedDept = departments.find((d: any) => d.id === form.departmentId)
+  const hasChange = (form.departmentId && form.departmentId !== employee.departmentId) ||
+                    (form.newPosition && form.newPosition !== employee.position)
+
   const handleSubmit = () => {
     onSubmit({
-      newDepartment: form.newDepartment,
-      effectiveDate: new Date(form.effectiveDate).toISOString(),
+      departmentId: form.departmentId || undefined,
+      newDepartment: selectedDept?.name || employee.department,
+      newPosition: form.newPosition || undefined,
+      effectiveMonth: form.effectiveDate.slice(0, 7),
       reason: form.reason || undefined,
     })
   }
 
-  const canSubmit = form.newDepartment && form.effectiveDate && form.newDepartment !== employee.department
+  const canSubmit = form.effectiveDate && hasChange
 
   return (
-    <Modal open onClose={onClose} title={`调部门 - ${employee.name}`}>
+    <Modal open onClose={onClose} title={`调动 - ${employee.name}`}>
       <div className="space-y-3">
         <div className="grid grid-cols-2 gap-3">
           <div>
@@ -107,23 +140,37 @@ export function DeptChangeModal({ employee, onClose, onSubmit, loading, error }:
             <div className="text-xs text-gray-600 py-1.5">{employee.name}</div>
           </div>
           <div>
-            <Label>当前部门</Label>
-            <div className="text-xs text-gray-600 py-1.5">{employee.department}</div>
+            <Label>当前部门 / 职务</Label>
+            <div className="text-xs text-gray-600 py-1.5">{employee.department} / {employee.position || '—'}</div>
           </div>
         </div>
         <div className="grid grid-cols-2 gap-3">
           <div>
-            <Label>新部门 *</Label>
-            <Input value={form.newDepartment} onChange={(e) => setForm({ ...form, newDepartment: e.target.value })} placeholder="如：市场部" />
+            <Label>目标部门 *</Label>
+            <Select value={form.departmentId} onChange={(e) => setForm({ ...form, departmentId: e.target.value })}>
+              <option value="">请选择部门</option>
+              {deptOptions.map(d => (
+                <option key={d.id} value={d.id}>{'　'.repeat(d.level)}{d.label}</option>
+              ))}
+            </Select>
           </div>
           <div>
-            <Label>生效日期 *</Label>
-            <Input type="date" value={form.effectiveDate} onChange={(e) => setForm({ ...form, effectiveDate: e.target.value })} />
+            <Label>新职务</Label>
+            <Select value={form.newPosition} onChange={(e) => setForm({ ...form, newPosition: e.target.value })}>
+              <option value="">保持不变</option>
+              {filteredPositions.map((p: any) => (
+                <option key={p.id} value={p.name}>{p.name}{p.level ? `（${p.level}）` : ''}</option>
+              ))}
+            </Select>
           </div>
         </div>
         <div>
-          <Label>调部门原因（选填）</Label>
-          <Input value={form.reason} onChange={(e) => setForm({ ...form, reason: e.target.value })} placeholder="如：组织架构调整" />
+          <Label>生效日期 *</Label>
+          <Input type="date" value={form.effectiveDate} onChange={(e) => setForm({ ...form, effectiveDate: e.target.value })} />
+        </div>
+        <div>
+          <Label>调动原因（选填）</Label>
+          <Input value={form.reason} onChange={(e) => setForm({ ...form, reason: e.target.value })} placeholder="如：组织架构调整、岗位轮换" />
         </div>
         {error && (
           <div className="text-xs text-danger">
@@ -132,7 +179,7 @@ export function DeptChangeModal({ employee, onClose, onSubmit, loading, error }:
         )}
         <div className="flex justify-end gap-2 pt-2">
           <Button variant="secondary" onClick={onClose}>取消</Button>
-          <Button onClick={handleSubmit} disabled={loading || !canSubmit}>{loading ? '保存中...' : '确认调部门'}</Button>
+          <Button onClick={handleSubmit} disabled={loading || !canSubmit}>{loading ? '保存中...' : '确认调动'}</Button>
         </div>
       </div>
     </Modal>