feat: 初始化项目结构并添加核心功能模块

- 新增文档模板和导航结构
- 实现服务器基础API路由和控制器
- 添加扩展插件配置和前端框架
- 引入多租户和权限管理模块
- 集成日志和数据库配置
- 添加核心业务模型和类型定义

server/src/services/PaymentRiskService.ts

@@ -0,0 +1,50 @@
+import db from '../config/database';
+import { logger } from '../utils/logger';
+import { DecisionExplainabilityEngine } from '../core/ai/DecisionExplainabilityEngine';
+
+/**
+ * [BIZ_OPS_153] 高频取消订单导致的支付网关风险预警 (Gateway)
+ * @description 核心逻辑：分析支付网关的回调日志，识别是否存在大量“取消”、“拒付”或“退款”，这些行为可能导致 PayPal/Stripe 账户被封。
+ */
+export class PaymentRiskService {
+  /**
+   * 监控支付网关风险 (BIZ_OPS_153)
+   */
+  static async monitorPaymentGatewayRisk(tenantId: string, gatewayId: string): Promise<any> {
+    logger.info(`[PaymentRisk] Monitoring gateway risk for Tenant: ${tenantId}, Gateway: ${gatewayId}`);
+
+    try {
+      // 1. 获取近 7 天的取消率 (模拟)
+      const cancellationRate = 0.15; // 15% 取消率
+      const threshold = 0.10;
+
+      // 2. 识别风险：如果超过 10%
+      if (cancellationRate > threshold) {
+        const advice = `GATEWAY RISK ALERT: Cancellation rate (${(cancellationRate * 100).toFixed(1)}%) is above the safe threshold (10%). ` +
+          `High risk of account suspension by the payment provider (PayPal/Stripe). ` +
+          `Suggesting immediate pause of high-risk traffic or increased anti-fraud review.`;
+
+        // 3. [UX_XAI_01] 记录决策证据链
+        await DecisionExplainabilityEngine.logDecision({
+          tenantId,
+          module: 'PAYMENT_SECURITY',
+          resourceId: gatewayId,
+          decisionType: 'GATEWAY_SUSPENSION_PREVENTION',
+          causalChain: advice,
+          factors: [
+            { name: 'CancellationRate', value: (cancellationRate * 100).toFixed(1) + '%', weight: 0.9, impact: 'NEGATIVE' },
+            { name: 'ThresholdRate', value: (threshold * 100).toFixed(1) + '%', weight: 0.1, impact: 'NEUTRAL' }
+          ],
+          traceId: 'payment-risk-' + Date.now()
+        });
+
+        return { success: true, riskLevel: 'HIGH', cancellationRate, advice, status: 'PENDING_REVIEW' };
+      }
+
+      return { success: true, riskLevel: 'LOW', message: 'Gateway risk is within limits' };
+    } catch (err: any) {
+      logger.error(`[PaymentRisk][WARN] Monitoring failed: ${err.message}`);
+      return { success: false, error: err.message };
+    }
+  }
+}