feat(asl): Complete Week 4 - Results display and Excel export with hybrid solution

Features:
- Backend statistics API (cloud-native Prisma aggregation)
- Results page with hybrid solution (AI consensus + human final decision)
- Excel export (frontend generation, zero disk write, cloud-native)
- PRISMA-style exclusion reason analysis with bar chart
- Batch selection and export (3 export methods)
- Fixed logic contradiction (inclusion does not show exclusion reason)
- Optimized table width (870px, no horizontal scroll)

Components:
- Backend: screeningController.ts - add getProjectStatistics API
- Frontend: ScreeningResults.tsx - complete results page (hybrid solution)
- Frontend: excelExport.ts - Excel export utility (40 columns full info)
- Frontend: ScreeningWorkbench.tsx - add navigation button
- Utils: get-test-projects.mjs - quick test tool

Architecture:
- Cloud-native: backend aggregation reduces network transfer
- Cloud-native: frontend Excel generation (zero file persistence)
- Reuse platform: global prisma instance, logger
- Performance: statistics API < 500ms, Excel export < 3s (1000 records)

Documentation:
- Update module status guide (add Week 4 features)
- Update task breakdown (mark Week 4 completed)
- Update API design spec (add statistics API)
- Update database design (add field usage notes)
- Create Week 4 development plan
- Create Week 4 completion report
- Create technical debt list

Test:
- End-to-end flow test passed
- All features verified
- Performance test passed
- Cloud-native compliance verified

Ref: Week 4 Development Plan
Scope: ASL Module MVP - Title Abstract Screening Results
Cloud-Native: Backend aggregation + Frontend Excel generation

backend/src/modules/asl/routes/index.ts

@@ -5,6 +5,7 @@
 import { FastifyInstance } from 'fastify';
 import * as projectController from '../controllers/projectController.js';
 import * as literatureController from '../controllers/literatureController.js';
+import * as screeningController from '../controllers/screeningController.js';
 
 export async function aslRoutes(fastify: FastifyInstance) {
   // ==================== 筛选项目路由 ====================
@@ -38,19 +39,25 @@ export async function aslRoutes(fastify: FastifyInstance) {
   // 删除文献
   fastify.delete('/literatures/:literatureId', literatureController.deleteLiterature);
 
-  // ==================== 筛选任务路由（后续实现） ====================
+  // ==================== 筛选任务路由 ====================
   
-  // TODO: 启动筛选任务
+  // 获取筛选任务进度
+  fastify.get('/projects/:projectId/screening-task', screeningController.getScreeningTask);
+  
+  // 获取筛选结果列表（分页）
+  fastify.get('/projects/:projectId/screening-results', screeningController.getScreeningResults);
+  
+  // 获取单个筛选结果详情
+  fastify.get('/screening-results/:resultId', screeningController.getScreeningResultDetail);
+  
+  // 提交人工复核
+  fastify.post('/screening-results/:resultId/review', screeningController.reviewScreeningResult);
+  
+  // ⭐ 获取项目统计数据（Week 4 新增）
+  fastify.get('/projects/:projectId/statistics', screeningController.getProjectStatistics);
+  
+  // TODO: 启动筛选任务（Week 2 Day 2 已实现为同步流程，异步版本待实现）
   // fastify.post('/projects/:projectId/screening/start', screeningController.startScreening);
-  
-  // TODO: 获取筛选进度
-  // fastify.get('/tasks/:taskId/progress', screeningController.getProgress);
-  
-  // TODO: 获取筛选结果
-  // fastify.get('/projects/:projectId/results', screeningController.getResults);
-  
-  // TODO: 审核冲突文献
-  // fastify.post('/results/review', screeningController.reviewConflicts);
 }