feat: AI预测分析接入真实后端数据 + 修复CloudBilling文件损坏

- AIPredictiveAnalytics: 替换3组硬编码mock为实时数据驱动预测
  - 指标预测: 基于dashboard metrics时序数据(cpu/memory/disk)线性回归计算斜率与R²
  - 容量规划: 基于日均增长率推算阈值触及时间(天),动态生成AI扩容建议
  - 异常预测: 基于告警规则阈值+当前趋势+事件频率计算异常触发概率
  - 概览卡片数据驱动化(置信度基于R²拟合度,高风险/容量预警计数实时计算)
- CloudBilling.tsx: 修复read_file导致的行号前缀损坏(501行全部含N|前缀)

backend/internal/api/routes/routes.go

@@ -68,6 +68,7 @@ func Register(r *gin.Engine, db *gorm.DB, log *zap.Logger, cfg *config.Config) {
 		ldapGroup.POST("/create-ou", ldapHandler.CreateLDAPOU)
 		ldapGroup.POST("/create-user", ldapHandler.CreateLDAPUser)
 		ldapGroup.POST("/delete-user", ldapHandler.DeleteLDAPUser)
+		ldapGroup.POST("/update-user", ldapHandler.UpdateLDAPUser)
 	}
 
 	// 仪表盘路由
@@ -133,6 +134,26 @@ func Register(r *gin.Engine, db *gorm.DB, log *zap.Logger, cfg *config.Config) {
 		regions.DELETE("/:id", regionHandler.DeleteRegion)
 	}
 
+	// 云账单路由
+	billingHandler := handlers.NewBillingHandler(db)
+	billings := authorized.Group("/cloud-billings")
+	{
+		billings.GET("", billingHandler.ListBillings)
+		billings.POST("", billingHandler.CreateBilling)
+		billings.POST("/batch", billingHandler.BatchCreateBillings)
+		billings.DELETE("/:id", billingHandler.DeleteBilling)
+		billings.GET("/stats", billingHandler.GetBillingStats)
+		billings.GET("/providers", billingHandler.GetProviderOptions)
+	}
+	billingAlerts := authorized.Group("/billing-alerts")
+	{
+		billingAlerts.GET("", billingHandler.ListAlertRules)
+		billingAlerts.POST("", billingHandler.CreateAlertRule)
+		billingAlerts.PUT("/:id", billingHandler.UpdateAlertRule)
+		billingAlerts.DELETE("/:id", billingHandler.DeleteAlertRule)
+		billingAlerts.POST("/:id/toggle", billingHandler.ToggleAlertRule)
+	}
+
 	// 资源模型路由
 	resourceModelHandler := handlers.NewResourceModelHandler(db)
 	resourceModels := authorized.Group("/resource-models")