feat(pkb): Complete PKB module frontend migration with V3 design

Summary:
- Implement PKB Dashboard and Workspace pages based on V3 prototype
- Add single-layer header with integrated Tab navigation
- Implement 3 work modes: Full Text, Deep Read, Batch Processing
- Integrate Ant Design X Chat component for AI conversations
- Create BatchModeComplete with template selection and document processing
- Add compact work mode selector with dropdown design

Backend:
- Migrate PKB controllers and services to /modules/pkb structure
- Register v2 API routes at /api/v2/pkb/knowledge
- Maintain dual API routes for backward compatibility

Technical details:
- Use Zustand for state management
- Handle SSE streaming responses for AI chat
- Support document selection for Deep Read mode
- Implement batch processing with progress tracking

Known issues:
- Batch processing API integration pending
- Knowledge assets page navigation needs optimization

Status: Frontend functional, pending refinement

backend/src/index.ts

@@ -12,6 +12,7 @@ import { batchRoutes } from './legacy/routes/batchRoutes.js';
 import reviewRoutes from './legacy/routes/reviewRoutes.js';
 import { aslRoutes } from './modules/asl/routes/index.js';
 import { registerDCRoutes, initDCModule } from './modules/dc/index.js';
+import pkbRoutes from './modules/pkb/routes/index.js';
 import { registerHealthRoutes } from './common/health/index.js';
 import { logger } from './common/logging/index.js';
 import { registerTestRoutes } from './test-platform-api.js';
@@ -111,6 +112,13 @@ await fastify.register(batchRoutes, { prefix: '/api/v1' });
 // 注册稿件审查路由
 await fastify.register(reviewRoutes, { prefix: '/api/v1' });
 
+// ============================================
+// 【业务模块】PKB - 个人知识库（新架构 v2）
+// ============================================
+await fastify.register(pkbRoutes, { prefix: '/api/v2/pkb' });
+logger.info('✅ PKB个人知识库路由已注册（v2新架构）: /api/v2/pkb');
+logger.info('   ⚠️  旧版路由仍可用: /api/v1/knowledge, /api/v1/batch-tasks');
+
 // ============================================
 // 【业务模块】ASL - AI智能文献筛选
 // ============================================