feat: 完善多云资产与腾讯云账单同步

- 接入 AWS、腾讯云、华为云和 Azure 区域及主机发现
- 接入腾讯云账单分页、限流与组件费用汇总
- 批量账单仅同步已支持厂商并优化云账号操作

backend/cloud/billing.go

@@ -16,13 +16,16 @@ type BillingFetcher interface {
 	FetchDailyBill(billingDate string) ([]CloudBillingRecord, error)
 }
 
+// SupportedBillingProviders 已接入账单 API 的云厂商列表。 // Logan.Li
+var SupportedBillingProviders = []string{"aliyun", "tencent"}
+
 // NewBillingFetcher 根据云厂商创建账单拉取器
 func NewBillingFetcher(provider, accessKey, secretKey string) BillingFetcher {
 	switch provider {
 	case "aliyun":
-		if p := NewAliyunProvider(accessKey, secretKey); p != nil {
-			return p
-		}
+		return NewAliyunProvider(accessKey, secretKey)
+	case "tencent":
+		return NewTencentProvider(accessKey, secretKey)
 	}
 	return nil
-}
+}