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

frontend-v2/src/modules/iit/pages/DashboardPage.tsx

@@ -5,7 +5,7 @@
  */
 
 import React, { useState, useEffect, useCallback } from 'react';
-import { useSearchParams, useNavigate } from 'react-router-dom';
+import { useNavigate } from 'react-router-dom';
 import {
   Card,
   Row,
@@ -31,13 +31,13 @@ import {
   FileSearchOutlined,
 } from '@ant-design/icons';
 import * as iitProjectApi from '../api/iitProjectApi';
+import { useIitProject } from '../context/IitProjectContext';
 
 const { Text, Title } = Typography;
 
 const DashboardPage: React.FC = () => {
-  const [searchParams] = useSearchParams();
   const navigate = useNavigate();
-  const projectId = searchParams.get('projectId') || '';
+  const { projectId } = useIitProject();
 
   const [stats, setStats] = useState<any>(null);
   const [heatmap, setHeatmap] = useState<any>(null);
@@ -79,10 +79,6 @@ const DashboardPage: React.FC = () => {
   const healthColor = healthScore >= 80 ? '#52c41a' : healthScore >= 60 ? '#faad14' : '#ff4d4f';
   const healthLabel = healthScore >= 80 ? '良好' : healthScore >= 60 ? '需关注' : '风险';
 
-  if (!projectId) {
-    return <div style={{ padding: 24 }}><Empty description="请先选择一个项目" /></div>;
-  }
-
   return (
     <div>
       {/* Health Score */}