feat(task): add adaptor billing interface and async settlement framework

Add three billing lifecycle methods to the TaskAdaptor interface:
- EstimateBilling: compute OtherRatios from user request before pricing
- AdjustBillingOnSubmit: adjust ratios from upstream submit response
- AdjustBillingOnComplete: determine final quota at task terminal state

Introduce BaseBilling as embeddable no-op default for adaptors without
custom billing. Move Sora/Ali OtherRatios logic from shared validation
into per-adaptor EstimateBilling implementations.

Add TaskBillingContext to persist pricing params (model_price, group_ratio,
other_ratios) in task private data for async polling settlement.

Extract RecalculateTaskQuota as a general-purpose delta settlement
function and unify polling billing via settleTaskBillingOnComplete
(adaptor-first, then token-based fallback).

relay/relay_task.go

@@ -128,8 +128,9 @@ func ResolveOriginTask(c *gin.Context, info *relaycommon.RelayInfo) *dto.TaskErr
 }
 
 // RelayTaskSubmit 完成 task 提交的全部流程（每次尝试调用一次）：
-// 刷新渠道元数据 → 确定 platform/adaptor → 验证请求 → 计算价格 →
-// 预扣费（仅首次，通过 info.Billing==nil 守卫）→ 构建/发送/解析上游请求。
+// 刷新渠道元数据 → 确定 platform/adaptor → 验证请求 →
+// 估算计费(EstimateBilling) → 计算价格 → 预扣费（仅首次）→
+// 构建/发送/解析上游请求 → 提交后计费调整(AdjustBillingOnSubmit)。
 // 控制器负责 defer Refund 和成功后 Settle。
 func RelayTaskSubmit(c *gin.Context, info *relaycommon.RelayInfo) (*TaskSubmitResult, *dto.TaskError) {
 	info.InitChannelMeta(c)
@@ -159,10 +160,20 @@ func RelayTaskSubmit(c *gin.Context, info *relaycommon.RelayInfo) (*TaskSubmitRe
 		info.PublicTaskID = model.GenerateTaskID()
 	}
 
-	// 4. 价格计算
+	// 4. 价格计算：基础模型价格
 	info.OriginModelName = modelName
 	info.PriceData = helper.ModelPriceHelperPerCall(c, info)
 
+	// 5. 计费估算：让适配器根据用户请求提供 OtherRatios（时长、分辨率等）
+	//    必须在 ModelPriceHelperPerCall 之后调用（它会重建 PriceData）。
+	//    ResolveOriginTask 可能已在 remix 路径中预设了 OtherRatios，此处合并。
+	if estimatedRatios := adaptor.EstimateBilling(c, info); len(estimatedRatios) > 0 {
+		for k, v := range estimatedRatios {
+			info.PriceData.AddOtherRatio(k, v)
+		}
+	}
+
+	// 6. 将 OtherRatios 应用到基础额度
 	if !common.StringsContains(constant.TaskPricePatches, modelName) {
 		for _, ra := range info.PriceData.OtherRatios {
 			if ra != 1.0 {
@@ -171,7 +182,7 @@ func RelayTaskSubmit(c *gin.Context, info *relaycommon.RelayInfo) (*TaskSubmitRe
 		}
 	}
 
-	// 5. 预扣费（仅首次 — 重试时 info.Billing 已存在，跳过）
+	// 7. 预扣费（仅首次 — 重试时 info.Billing 已存在，跳过）
 	if info.Billing == nil && !info.PriceData.FreeModel {
 		info.ForcePreConsume = true
 		if apiErr := service.PreConsumeBilling(c, info.PriceData.Quota, info); apiErr != nil {
@@ -179,13 +190,13 @@ func RelayTaskSubmit(c *gin.Context, info *relaycommon.RelayInfo) (*TaskSubmitRe
 		}
 	}
 
-	// 6. 构建请求体
+	// 8. 构建请求体
 	requestBody, err := adaptor.BuildRequestBody(c, info)
 	if err != nil {
 		return nil, service.TaskErrorWrapper(err, "build_request_failed", http.StatusInternalServerError)
 	}
 
-	// 7. 发送请求
+	// 9. 发送请求
 	resp, err := adaptor.DoRequest(c, info, requestBody)
 	if err != nil {
 		return nil, service.TaskErrorWrapper(err, "do_request_failed", http.StatusInternalServerError)
@@ -195,20 +206,59 @@ func RelayTaskSubmit(c *gin.Context, info *relaycommon.RelayInfo) (*TaskSubmitRe
 		return nil, service.TaskErrorWrapper(fmt.Errorf("%s", string(responseBody)), "fail_to_fetch_task", resp.StatusCode)
 	}
 
-	// 8. 解析响应
+	// 10. 返回 OtherRatios 给下游（header 必须在 DoResponse 写 body 之前设置）
+	otherRatios := info.PriceData.OtherRatios
+	if otherRatios == nil {
+		otherRatios = map[string]float64{}
+	}
+	ratiosJSON, _ := common.Marshal(otherRatios)
+	c.Header("X-New-Api-Other-Ratios", string(ratiosJSON))
+
+	// 11. 解析响应
 	upstreamTaskID, taskData, taskErr := adaptor.DoResponse(c, resp, info)
 	if taskErr != nil {
 		return nil, taskErr
 	}
 
+	// 11. 提交后计费调整：让适配器根据上游实际返回调整 OtherRatios
+	finalQuota := info.PriceData.Quota
+	if adjustedRatios := adaptor.AdjustBillingOnSubmit(info, taskData); len(adjustedRatios) > 0 {
+		// 基于调整后的 ratios 重新计算 quota
+		finalQuota = recalcQuotaFromRatios(info, adjustedRatios)
+		info.PriceData.OtherRatios = adjustedRatios
+		info.PriceData.Quota = finalQuota
+	}
+
 	return &TaskSubmitResult{
 		UpstreamTaskID: upstreamTaskID,
 		TaskData:       taskData,
 		Platform:       platform,
 		ModelName:      modelName,
+		Quota:          finalQuota,
 	}, nil
 }
 
+// recalcQuotaFromRatios 根据 adjustedRatios 重新计算 quota。
+// 公式: baseQuota × ∏(ratio) — 其中 baseQuota 是不含 OtherRatios 的基础额度。
+func recalcQuotaFromRatios(info *relaycommon.RelayInfo, ratios map[string]float64) int {
+	// 从 PriceData 获取不含 OtherRatios 的基础价格
+	baseQuota := info.PriceData.Quota
+	// 先除掉原有的 OtherRatios 恢复基础额度
+	for _, ra := range info.PriceData.OtherRatios {
+		if ra != 1.0 && ra > 0 {
+			baseQuota = int(float64(baseQuota) / ra)
+		}
+	}
+	// 应用新的 ratios
+	result := float64(baseQuota)
+	for _, ra := range ratios {
+		if ra != 1.0 {
+			result *= ra
+		}
+	}
+	return int(result)
+}
+
 var fetchRespBuilders = map[int]func(c *gin.Context) (respBody []byte, taskResp *dto.TaskError){
 	relayconstant.RelayModeSunoFetchByID:  sunoFetchByIDRespBodyBuilder,
 	relayconstant.RelayModeSunoFetch:      sunoFetchRespBodyBuilder,