feat: 添加历史管理和用户评估记录API

- GET /assessment/history: 获取用户评估历史(保留最近100条)
- cleanupOldSessions: 保持最多3条记录(在创建新session时自动清理)
- 复查记录保留完整历史(reviewHistory)

server/src/assessment/assessment.controller.ts

@@ -135,6 +135,15 @@ export class AssessmentController {
     return this.assessmentService.generateCertificate(sessionId, userId, tenantId);
   }
 
+  @Get('history')
+  @ApiOperation({ summary: 'Get current user assessment history (keep latest 3)' })
+  async getHistory(
+    @Request() req: any,
+  ) {
+    const { id: userId } = req.user;
+    return this.assessmentService.getUserHistory(userId);
+  }
+
   @Get('stats')
   @ApiOperation({ summary: 'Get assessment statistics for admin' })
   async getStats(