feat: add version history section to test edit page

- GET /api/tests/{id}/versions — returns full version chain from oldest to newest
- TestEdit: shows 'История версий' table when multiple versions exist,
  current version highlighted, links to navigate between versions

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

frontend/src/pages/TestEdit/index.tsx

@@ -6,11 +6,12 @@ import {
   PlayCircleOutlined,
 } from '@ant-design/icons'
 import { useMutation, useQuery, useQueryClient } from '@tanstack/react-query'
-import { Alert, Button, Card, Descriptions, List, Space, Spin, Tag, Typography, message } from 'antd'
+import { Alert, Button, Card, Descriptions, List, Space, Spin, Table, Tag, Typography, message } from 'antd'
+import type { ColumnsType } from 'antd/es/table'
 import { useState } from 'react'
 import { useNavigate, useParams } from 'react-router-dom'
 
-import { Answer, CreateTestDto, testsApi } from '../../api/tests'
+import { Answer, CreateTestDto, TestListItem, testsApi } from '../../api/tests'
 import TestForm, { TestFormValues } from '../../components/TestForm'
 
 const { Title, Text } = Typography
@@ -26,6 +27,12 @@ export default function TestEdit() {
     queryFn: () => testsApi.get(Number(id)).then((r) => r.data),
   })
 
+  const { data: versions = [] } = useQuery({
+    queryKey: ['tests', id, 'versions'],
+    queryFn: () => testsApi.versions(Number(id)).then((r) => r.data),
+    enabled: !editMode,
+  })
+
   const { mutate: updateTest, isPending } = useMutation({
     mutationFn: (data: CreateTestDto) => testsApi.update(Number(id), data).then((r) => r.data),
     onSuccess: (result) => {
@@ -174,6 +181,66 @@ export default function TestEdit() {
           />
         </Card>
       ))}
+
+      {versions.length > 1 && (
+        <>
+          <Title level={3} style={{ marginTop: 32 }}>
+            История версий
+          </Title>
+          <Table<TestListItem>
+            dataSource={versions}
+            rowKey="id"
+            size="small"
+            pagination={false}
+            rowClassName={(record) => (record.id === test.id ? 'ant-table-row-selected' : '')}
+            columns={
+              [
+                {
+                  title: 'Версия',
+                  dataIndex: 'version',
+                  width: 90,
+                  render: (v: number, record: TestListItem) => (
+                    <Space>
+                      <Tag color={record.id === test.id ? 'blue' : 'default'}>v{v}</Tag>
+                      {record.id === test.id && <Text type="secondary">(текущая)</Text>}
+                    </Space>
+                  ),
+                },
+                {
+                  title: 'Дата',
+                  dataIndex: 'created_at',
+                  width: 120,
+                  render: (d: string) => new Date(d).toLocaleDateString('ru-RU'),
+                },
+                {
+                  title: 'Вопросов',
+                  dataIndex: 'questions_count',
+                  width: 100,
+                  align: 'center' as const,
+                },
+                {
+                  title: 'Порог зачёта',
+                  dataIndex: 'passing_score',
+                  width: 120,
+                  align: 'center' as const,
+                  render: (s: number) => `${s}%`,
+                },
+                {
+                  title: '',
+                  key: 'action',
+                  width: 100,
+                  render: (_: unknown, record: TestListItem) =>
+                    record.id !== test.id ? (
+                      <Button size="small" onClick={() => navigate(`/tests/${record.id}/edit`)}>
+                        Открыть
+                      </Button>
+                    ) : null,
+                },
+              ] as ColumnsType<TestListItem>
+            }
+          />
+        </>
+      )}
     </div>
   )
 }