fix: 管理员自定义价格的任务模型自动按次计费，不再乘 OtherRatios

当管理员为任务模型（如 sora_video2）设置了固定价格时，
之前会错误地将价格乘以 seconds/size 等 OtherRatios，
导致设置 $2/次 实际收费 $8（$2 × 4秒）。

新增 IsTaskPerCallBilling() 判断逻辑：
- 模型在 TASK_PRICE_PATCH 环境变量中 → 按次（兼容旧逻辑）
- 模型有管理员配置的价格且不在默认价格表中 → 自动按次
默认价格表中的模型（如 sora-2: $0.3）仍按原逻辑乘 OtherRatios。

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

controller/relay.go

@@ -22,6 +22,7 @@ import (
 	"github.com/QuantumNous/new-api/service"
 	"github.com/QuantumNous/new-api/setting"
 	"github.com/QuantumNous/new-api/setting/operation_setting"
+	"github.com/QuantumNous/new-api/setting/ratio_setting"
 	"github.com/QuantumNous/new-api/types"
 
 	"github.com/bytedance/gopkg/util/gopool"
@@ -581,7 +582,7 @@ func RelayTask(c *gin.Context) {
 			ModelRatio:      relayInfo.PriceData.ModelRatio,
 			OtherRatios:     relayInfo.PriceData.OtherRatios,
 			OriginModelName: relayInfo.OriginModelName,
-			PerCallBilling:  common.StringsContains(constant.TaskPricePatches, relayInfo.OriginModelName),
+			PerCallBilling:  ratio_setting.IsTaskPerCallBilling(relayInfo.OriginModelName),
 		}
 		task.Quota = result.Quota
 		task.Data = result.TaskData

relay/relay_task.go

@@ -19,6 +19,7 @@ import (
 	relayconstant "github.com/QuantumNous/new-api/relay/constant"
 	"github.com/QuantumNous/new-api/relay/helper"
 	"github.com/QuantumNous/new-api/service"
+	"github.com/QuantumNous/new-api/setting/ratio_setting"
 	"github.com/gin-gonic/gin"
 )
 
@@ -194,7 +195,8 @@ func RelayTaskSubmit(c *gin.Context, info *relaycommon.RelayInfo) (*TaskSubmitRe
 	}
 
 	// 6. 将 OtherRatios 应用到基础额度
-	if !common.StringsContains(constant.TaskPricePatches, modelName) {
+	//    按次计费模型（TaskPricePatches 或管理员自定义价格）跳过 OtherRatios 乘算
+	if !ratio_setting.IsTaskPerCallBilling(modelName) {
 		for _, ra := range info.PriceData.OtherRatios {
 			if ra != 1.0 {
 				info.PriceData.Quota = int(float64(info.PriceData.Quota) * ra)

service/task_billing.go

@@ -5,8 +5,6 @@ import (
 	"fmt"
 	"strings"
 
-	"github.com/QuantumNous/new-api/common"
-	"github.com/QuantumNous/new-api/constant"
 	"github.com/QuantumNous/new-api/logger"
 	"github.com/QuantumNous/new-api/model"
 	relaycommon "github.com/QuantumNous/new-api/relay/common"
@@ -20,7 +18,7 @@ func LogTaskConsumption(c *gin.Context, info *relaycommon.RelayInfo) {
 	tokenName := c.GetString("token_name")
 	logContent := fmt.Sprintf("操作 %s", info.Action)
 	// 支持任务仅按次计费
-	if common.StringsContains(constant.TaskPricePatches, info.OriginModelName) {
+	if ratio_setting.IsTaskPerCallBilling(info.OriginModelName) {
 		logContent = fmt.Sprintf("%s，按次计费", logContent)
 	} else {
 		if len(info.PriceData.OtherRatios) > 0 {

setting/ratio_setting/model_ratio.go

@@ -4,6 +4,7 @@ import (
 	"strings"
 
 	"github.com/QuantumNous/new-api/common"
+	"github.com/QuantumNous/new-api/constant"
 	"github.com/QuantumNous/new-api/setting/operation_setting"
 	"github.com/QuantumNous/new-api/types"
 )
@@ -732,3 +733,20 @@ func GetModelRatioOrPrice(model string) (float64, bool, bool) { // price or rati
 	}
 	return 37.5, false, false
 }
+
+// IsTaskPerCallBilling 判断任务模型是否按次计费（固定价格，不乘 OtherRatios）。
+// 满足以下任一条件即为按次计费：
+//  1. 模型在 TaskPricePatches 列表中（环境变量配置）
+//  2. 模型有管理员配置的固定价格（在价格表中但不在默认价格表中）
+func IsTaskPerCallBilling(modelName string) bool {
+	if common.StringsContains(constant.TaskPricePatches, modelName) {
+		return true
+	}
+	// 检查模型是否有管理员配置的固定价格（非默认价格）
+	_, hasPrice := GetModelPrice(modelName, false)
+	if !hasPrice {
+		return false
+	}
+	_, isDefault := defaultModelPrice[modelName]
+	return !isDefault
+}