feat: 员工端密码登录完整支持

1. createEmployee 创建员工时自动设置默认密码（手机号后6位）
2. 管理员重置密码接口 POST /employees/:id/reset-password
   （重置为手机号后6位）
3. 员工自己修改密码接口 POST /portal/change-password
   （需验证旧密码，新密码至少6位）
4. 花名册详情添加"重置密码"按钮，显示默认密码提示
5. 员工端导航栏添加"修改密码"入口，弹窗修改密码

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

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

frontend/src/pages/roster/BasicInfo.tsx

@@ -9,7 +9,7 @@ import api from '../../lib/api'
 import Card from "../../components/ui/Card"
 import Button from "../../components/ui/Button"
 import { Input, Label, Select } from "../../components/ui/Input"
-import { AlertTriangle, Paperclip, Trash2, Eye, Download, Copy } from "lucide-react"
+import { AlertTriangle, Paperclip, Trash2, Eye, Download, Copy, KeyRound } from "lucide-react"
 import { fmt } from "./shared"
 
 export default function BasicInfo({ profile, employeeId, attachments }: { profile: any; employeeId: string; attachments: any[] }) {
@@ -29,6 +29,13 @@ export default function BasicInfo({ profile, employeeId, attachments }: { profil
     onSuccess: () => queryClient.invalidateQueries({ queryKey: ['roster-profile', employeeId] }),
   })
 
+  /** 重置员工密码（重置为手机号后6位） */
+  const resetPasswordMutation = useMutation({
+    mutationFn: () => employeeApi.resetPassword(employeeId),
+    onSuccess: (data: any) => toast.success(data?.message || '密码已重置'),
+    onError: (err: any) => toast.error(err?.response?.data?.error?.message || '重置失败'),
+  })
+
   const handleFileUpload = (e: React.ChangeEvent<HTMLInputElement>) => {
     const file = e.target.files?.[0]
     if (!file) return
@@ -493,12 +500,29 @@ export default function BasicInfo({ profile, employeeId, attachments }: { profil
         <div className="mt-4 pt-4 border-t">
           <div className="flex items-center justify-between mb-3">
             <h3 className="text-xs font-medium text-gray-600">员工端入口</h3>
-            <Button size="sm" variant="secondary" onClick={() => {
-              const url = `${window.location.origin}/portal/login`
-              navigator.clipboard?.writeText(url)
-            }}>
-              复制链接
-            </Button>
+            <div className="flex gap-2">
+              <Button size="sm" variant="secondary" onClick={() => {
+                const url = `${window.location.origin}/portal/login`
+                navigator.clipboard?.writeText(url)
+              }}>
+                复制链接
+              </Button>
+              <Button
+                size="sm"
+                variant="secondary"
+                onClick={async () => {
+                  const ok = await confirm({
+                    title: '重置员工密码',
+                    message: `将重置「${profile.name}」的员工端密码为手机号后6位（${profile.phone?.slice(-6)}），确认操作？`,
+                  })
+                  if (ok) resetPasswordMutation.mutate()
+                }}
+                disabled={resetPasswordMutation.isPending}
+              >
+                <KeyRound className="w-3.5 h-3.5 mr-1" />
+                重置密码
+              </Button>
+            </div>
           </div>
           <div className="flex items-center gap-4">
             <div className="bg-white p-3 rounded-lg border">
@@ -509,7 +533,8 @@ export default function BasicInfo({ profile, employeeId, attachments }: { profil
               />
             </div>
             <div className="text-xs text-gray-500 space-y-1">
-              <p>员工扫码进入员工端，使用手机号登录</p>
+              <p>员工扫码进入员工端，使用手机号+密码登录</p>
+              <p>默认密码：手机号后6位（{profile.phone?.slice(-6)}），员工可在端内自行修改</p>
               <p>可查看工资条、合同信息、确认签署</p>
               <p className="text-gray-400">链接：{window.location.origin}/portal/login</p>
             </div>