fix: code review — 7 issues resolved

(C1) Add dimensionScores/radarData/passed columns to AssessmentSession
(C2) Mock DataSource in service.spec.ts + app.e2e-spec.ts
(C3) Mock AuditLogService in controller.spec.ts
(C4) Rewrite deleteSession tests for dataSource.transaction
(I1) batchDeleteSessions uses transaction with certificate cleanup
(I2) extractDimensionScores reads from session property
(I3/I5) PDF generator supports multi-page + newline splitting
(I4) findOne inside transaction uses deleteCondition

server/src/assessment/services/export.service.ts

@@ -96,7 +96,7 @@ export class ExportService {
   }
 
   private extractDimensionScores(session: AssessmentSession): any[][] {
-    const scores = session.templateJson?.dimensionScores || session.finalReport;
+    const scores = (session as any).dimensionScores;
     if (!scores) return [['未找到维度分数']];
 
     if (typeof scores === 'string') {