feat(asl): Add DeepSearch smart literature retrieval MVP

Features:
- Integrate unifuncs DeepSearch API (OpenAI compatible protocol)
- SSE real-time streaming for AI thinking process display
- Natural language input, auto-generate PubMed search strategy
- Extract and display PubMed literature links
- Database storage for task records (asl_research_tasks)

Backend:
- researchService.ts - Core business logic with SSE streaming
- researchController.ts - SSE stream endpoint
- researchWorker.ts - Async task worker (backup mode)
- schema.prisma - AslResearchTask model

Frontend:
- ResearchSearch.tsx - Search page with unified content stream
- ResearchSearch.css - Styling (unifuncs-inspired simple design)
- ASLLayout.tsx - Enable menu item
- api/index.ts - Add research API functions

API Endpoints:
- POST /api/v1/asl/research/stream - SSE streaming search
- POST /api/v1/asl/research/tasks - Async task creation
- GET /api/v1/asl/research/tasks/:taskId/status - Task status

Documentation:
- Development record for DeepSearch integration
- Update ASL module status (v1.5)
- Update system status (v3.7)

Known limitations:
- SSE mode, task interrupts when leaving page
- Cost ~0.3 RMB per search (unifuncs API)

backend/src/index.ts

@@ -21,6 +21,7 @@ import { authRoutes, registerAuthPlugin } from './common/auth/index.js';
 import { promptRoutes } from './common/prompt/index.js';
 import { registerTestRoutes } from './test-platform-api.js';
 import { registerScreeningWorkers } from './modules/asl/services/screeningWorker.js';
+import { registerResearchWorker } from './modules/asl/workers/researchWorker.js';
 import { registerExtractionWorkers } from './modules/dc/tool-b/workers/extractionWorker.js';
 import { registerParseExcelWorker } from './modules/dc/tool-c/workers/parseExcelWorker.js';
 import { registerReviewWorker } from './modules/rvw/workers/reviewWorker.js';
@@ -206,6 +207,10 @@ const start = async () => {
       registerScreeningWorkers();
       logger.info('✅ ASL screening workers registered');
       
+      // 注册ASL智能文献检索Worker
+      registerResearchWorker();
+      logger.info('✅ ASL research worker registered');
+      
       // 注册DC提取Workers
       registerExtractionWorkers();
       logger.info('✅ DC extraction workers registered');