feat(iit): QC deep fix + V3.1 architecture plan + project member management

QC System Deep Fix:
- HardRuleEngine: add null tolerance + field availability pre-check (skipped status)
- SkillRunner: baseline data merge for follow-up events + field availability check
- QcReportService: record-level pass rate calculation + accurate LLM XML report
- iitBatchController: legacy log cleanup (eventId=null) + upsert RecordSummary
- seed-iit-qc-rules: null/empty string tolerance + applicableEvents config

V3.1 Architecture Design (docs only, no code changes):
- QC engine V3.1 plan: 5-level data structure (CDISC ODM) + D1-D7 dimensions
- Three-batch implementation strategy (A: foundation, B: bubbling, C: new engines)
- Architecture team review: 4 whitepapers reviewed + feedback doc + 4 critical suggestions
- CRA Agent strategy roadmap + CRA 4-tool explanation doc for clinical experts

Project Member Management:
- Cross-tenant member search and assignment (remove tenant restriction)
- IIT project detail page enhancement with tabbed layout (KB + members)
- IitProjectContext for business-side project selection
- System-KB route access control adjustment for project operators

Frontend:
- AdminLayout sidebar menu restructure
- IitLayout with project context provider
- IitMemberManagePage new component
- Business-side pages adapt to project context

Prisma:
- 2 new migrations (user-project RBAC + is_demo flag)
- Schema updates for project member management

Made-with: Cursor

backend/src/modules/admin/system-kb/systemKbRoutes.ts

@@ -19,8 +19,8 @@ import {
 import { authenticate, requireRoles } from '../../../common/auth/auth.middleware.js';
 
 export async function systemKbRoutes(fastify: FastifyInstance) {
-  // 所有路由都需要认证 + SUPER_ADMIN 或 ADMIN 角色
-  const preHandler = [authenticate, requireRoles('SUPER_ADMIN', 'ADMIN')];
+  // 认证 + 角色守卫：SUPER_ADMIN / ADMIN / IIT_OPERATOR 均可完整操作知识库
+  const preHandler = [authenticate, requireRoles('SUPER_ADMIN', 'ADMIN', 'IIT_OPERATOR')];
 
   // ==================== 知识库 CRUD ====================