feat: add question export foundation

scripts/api-integration-test.js

@@ -2253,6 +2253,16 @@ async function testTenantContentAdmin() {
       correctOptionIndices: [1],
       answerText: '4',
       explanation: '基础加法。',
+      subQuestions: [
+        {
+          type: 'choice',
+          content: '集成测试子题：1 + 1 = ?',
+          options: ['1', '2'],
+          correctOptionIndices: [1],
+          answerText: '2',
+          explanation: '子题基础加法。',
+        },
+      ],
       status: 'published',
       examMarkers: { schoolName: '集成测试学院', salesIntent: true },
     },
@@ -2312,6 +2322,118 @@ async function testTenantContentAdmin() {
   });
   assert.ok(publicCreatedCollections.items?.some(item => item.id === collection.item.id), 'catalog should expose created collection');
 
+  const exportDenied = await request('/api/tenant-content/exports/questions', {
+    method: 'POST',
+    body: { scopeType: 'collection', scopeId: collection.item.id },
+    expectStatus: 403,
+  });
+  assert.equal(exportDenied.code, 'TENANT_CONTENT_EDITOR_REQUIRED', 'student should not export tenant question bank content');
+
+  const exportNoAnswers = await request('/api/tenant-content/exports/questions', {
+    userId: TENANT_ADMIN_USER_ID,
+    method: 'POST',
+    body: {
+      scopeType: 'collection',
+      scopeId: collection.item.id,
+      format: 'json',
+      exportType: 'questions',
+      includeAnswers: false,
+      includeExplanations: false,
+      options: { title: '集成测试无答案题库导出' },
+    },
+  });
+  assert.equal(exportNoAnswers.job?.status, 'completed', 'question export should create a completed export job');
+  assert.equal(exportNoAnswers.export?.summary?.questionCount, 1, 'question export should include collection questions');
+  assert.ok(exportNoAnswers.export?.files?.[0]?.contentBase64, 'question export should return a downloadable JSON payload');
+  assert.equal(
+    Object.hasOwn(exportNoAnswers.export?.questions?.[0] || {}, 'answerText'),
+    false,
+    'question export should omit answers when includeAnswers is false',
+  );
+  assert.equal(
+    Object.hasOwn(exportNoAnswers.export?.questions?.[0] || {}, 'explanation'),
+    false,
+    'question export should omit explanations when includeExplanations is false',
+  );
+  assert.equal(
+    Object.hasOwn(exportNoAnswers.export?.questions?.[0]?.subQuestions?.[0] || {}, 'correctOptionIndices'),
+    false,
+    'question export should omit sub question answers when includeAnswers is false',
+  );
+  assert.equal(
+    Object.hasOwn(exportNoAnswers.export?.questions?.[0]?.subQuestions?.[0] || {}, 'answerText'),
+    false,
+    'question export should omit sub question answer text when includeAnswers is false',
+  );
+  assert.equal(
+    Object.hasOwn(exportNoAnswers.export?.questions?.[0]?.subQuestions?.[0] || {}, 'explanation'),
+    false,
+    'question export should omit sub question explanations when includeExplanations is false',
+  );
+  const decodedExport = JSON.parse(Buffer.from(exportNoAnswers.export.files[0].contentBase64, 'base64').toString('utf8'));
+  assert.equal(decodedExport._tikuExport, '3.0', 'question export JSON should use the new export contract');
+  assert.equal(decodedExport.questions?.[0]?.content, '集成测试题：2 + 2 = ?', 'question export JSON should include question content');
+
+  const exportBadLimit = await request('/api/tenant-content/exports/questions', {
+    userId: TENANT_ADMIN_USER_ID,
+    method: 'POST',
+    body: {
+      scopeType: 'collection',
+      scopeId: collection.item.id,
+      limit: 'not-a-number',
+    },
+  });
+  assert.equal(exportBadLimit.export?.summary?.questionCount, 1, 'question export should tolerate invalid limit input with a safe default');
+
+  const paperExport = await request('/api/tenant-content/exports/questions', {
+    userId: TENANT_ADMIN_USER_ID,
+    method: 'POST',
+    body: {
+      scopeType: 'content_node',
+      scopeId: childNode.item.id,
+      format: 'paper_json',
+      exportType: 'paper',
+      includeAnswers: true,
+      includeExplanations: true,
+      options: {
+        title: '集成测试试卷版导出',
+        durationMinutes: 90,
+        watermarkText: '仅供内部测试',
+      },
+    },
+  });
+  assert.equal(paperExport.export?.renderHints?.pdfLayout, 'paper', 'paper export should expose paper render hints');
+  assert.ok(
+    paperExport.export?.sections?.some(section => section.questions?.some(item => item.id === question.item.id)),
+    'paper export should group the created question by section',
+  );
+  const exportedQuestionWithAnswer = paperExport.export?.questions?.find(item => item.id === question.item.id);
+  assert.equal(exportedQuestionWithAnswer?.answerText, '4', 'paper export should include answers when requested');
+
+  const partnerExportDenied = await request('/api/tenant-content/exports/questions', {
+    tenantId: PARTNER_TENANT_ID,
+    userId: PARTNER_TENANT_ADMIN_USER_ID,
+    method: 'POST',
+    body: { scopeType: 'collection', scopeId: collection.item.id },
+    expectStatus: 404,
+  });
+  assert.equal(partnerExportDenied.code, 'QUESTION_COLLECTION_NOT_FOUND', 'question export must not read another tenant collection');
+
+  const exportJobs = await request('/api/tenant-content/exports/jobs', {
+    userId: TENANT_ADMIN_USER_ID,
+    query: { scopeType: 'collection', scopeId: collection.item.id, limit: 10 },
+  });
+  assert.ok(
+    exportJobs.items?.some(item => item.id === exportNoAnswers.job.id && item.questionCount === 1),
+    'question export jobs should list completed export audit records',
+  );
+  const invalidExportJobsScope = await request('/api/tenant-content/exports/jobs', {
+    userId: TENANT_ADMIN_USER_ID,
+    query: { scopeType: 'not_supported' },
+    expectStatus: 400,
+  });
+  assert.equal(invalidExportJobsScope.code, 'INVALID_EXPORT_SCOPE', 'question export jobs should validate scope type filters');
+
   const createdBlueprintSession = await request('/api/learning/practice-sessions', {
     method: 'POST',
     body: { userId: USER_ID, blueprintId: blueprint.item.id },