feat: add community enhancements — password reset, audit logs, multi-source backup

Three community-requested features:

1. CLI password reset: `backupx reset-password --username admin --password xxx`
   Docker users can run via `docker exec`. No full app init needed.

2. Audit logging: async fire-and-forget audit trail for all key operations
   (login, CRUD on tasks/targets/records, settings changes).
   New UI page at /audit with category filter and pagination.

3. Multi-source path backup: file backup tasks now support multiple source
   directories packed into a single tar archive. Backward compatible with
   existing single sourcePath field.

web/src/pages/audit/AuditLogsPage.tsx

@@ -0,0 +1,154 @@
+import { PageHeader, Select, Space, Table, Tag, Typography } from '@arco-design/web-react'
+import type { ColumnProps } from '@arco-design/web-react/es/Table'
+import { useCallback, useEffect, useState } from 'react'
+import { listAuditLogs } from '../../services/audit'
+import type { AuditLog } from '../../types/audit'
+import { formatDateTime } from '../../utils/format'
+import { resolveErrorMessage } from '../../utils/error'
+
+const categoryOptions = [
+  { label: '全部', value: '' },
+  { label: '认证', value: 'auth' },
+  { label: '存储目标', value: 'storage_target' },
+  { label: '备份任务', value: 'backup_task' },
+  { label: '备份记录', value: 'backup_record' },
+  { label: '系统设置', value: 'settings' },
+]
+
+const categoryLabels: Record<string, string> = {
+  auth: '认证',
+  storage_target: '存储目标',
+  backup_task: '备份任务',
+  backup_record: '备份记录',
+  settings: '系统设置',
+}
+
+const actionLabels: Record<string, string> = {
+  login_success: '登录成功',
+  login_failed: '登录失败',
+  setup: '系统初始化',
+  change_password: '修改密码',
+  create: '创建',
+  update: '更新',
+  delete: '删除',
+  enable: '启用',
+  disable: '停用',
+  run: '执行',
+  restore: '恢复',
+}
+
+const PAGE_SIZE = 20
+
+const columns: ColumnProps<AuditLog>[] = [
+  {
+    title: '时间',
+    dataIndex: 'createdAt',
+    width: 180,
+    render: (_, record) => formatDateTime(record.createdAt),
+  },
+  {
+    title: '分类',
+    dataIndex: 'category',
+    width: 100,
+    render: (_, record) => (
+      <Tag bordered>{categoryLabels[record.category] ?? record.category}</Tag>
+    ),
+  },
+  {
+    title: '操作',
+    dataIndex: 'action',
+    width: 100,
+    render: (_, record) => actionLabels[record.action] ?? record.action,
+  },
+  {
+    title: '用户',
+    dataIndex: 'username',
+    width: 100,
+  },
+  {
+    title: '目标',
+    dataIndex: 'targetName',
+    width: 160,
+    render: (_, record) => record.targetName || record.targetId || '-',
+  },
+  {
+    title: '详情',
+    dataIndex: 'detail',
+    render: (_, record) => record.detail || '-',
+  },
+  {
+    title: 'IP',
+    dataIndex: 'clientIp',
+    width: 130,
+    render: (_, record) => record.clientIp || '-',
+  },
+]
+
+export function AuditLogsPage() {
+  const [logs, setLogs] = useState<AuditLog[]>([])
+  const [total, setTotal] = useState(0)
+  const [loading, setLoading] = useState(true)
+  const [error, setError] = useState('')
+  const [category, setCategory] = useState('')
+  const [page, setPage] = useState(1)
+
+  const fetchData = useCallback(async (cat: string, currentPage: number) => {
+    setLoading(true)
+    try {
+      const result = await listAuditLogs({
+        category: cat || undefined,
+        limit: PAGE_SIZE,
+        offset: (currentPage - 1) * PAGE_SIZE,
+      })
+      setLogs(result.items ?? [])
+      setTotal(result.total ?? 0)
+      setError('')
+    } catch (loadError) {
+      setError(resolveErrorMessage(loadError, '加载审计日志失败'))
+    } finally {
+      setLoading(false)
+    }
+  }, [])
+
+  useEffect(() => {
+    void fetchData(category, page)
+  }, [category, page, fetchData])
+
+  function handleCategoryChange(value: string) {
+    setCategory(value)
+    setPage(1)
+  }
+
+  return (
+    <Space direction="vertical" size="large" style={{ width: '100%' }}>
+      <PageHeader
+        style={{ paddingBottom: 0 }}
+        title="审计日志"
+        subTitle="记录系统中所有关键操作，保障数据操作链可溯源"
+      />
+      {error ? <Typography.Text type="error">{error}</Typography.Text> : null}
+      <Space>
+        <Select
+          style={{ width: 160 }}
+          value={category}
+          options={categoryOptions}
+          onChange={handleCategoryChange}
+          placeholder="筛选分类"
+        />
+      </Space>
+      <Table
+        columns={columns}
+        data={logs}
+        rowKey="id"
+        loading={loading}
+        pagination={{
+          total,
+          current: page,
+          pageSize: PAGE_SIZE,
+          onChange: setPage,
+          showTotal: true,
+        }}
+      />
+    </Space>
+  )
+}