fix: preserve explicit zero values in native relay requests

relay/channel/openai/adaptor.go

@@ -29,6 +29,7 @@ import (
 	"github.com/QuantumNous/new-api/service"
 	"github.com/QuantumNous/new-api/setting/model_setting"
 	"github.com/QuantumNous/new-api/types"
+	"github.com/samber/lo"
 
 	"github.com/gin-gonic/gin"
 )
@@ -314,9 +315,9 @@ func (a *Adaptor) ConvertOpenAIRequest(c *gin.Context, info *relaycommon.RelayIn
 
 	}
 	if strings.HasPrefix(info.UpstreamModelName, "o") || strings.HasPrefix(info.UpstreamModelName, "gpt-5") {
-		if request.MaxCompletionTokens == 0 && request.MaxTokens != 0 {
+		if lo.FromPtrOr(request.MaxCompletionTokens, uint(0)) == 0 && lo.FromPtrOr(request.MaxTokens, uint(0)) != 0 {
 			request.MaxCompletionTokens = request.MaxTokens
-			request.MaxTokens = 0
+			request.MaxTokens = nil
 		}
 
 		if strings.HasPrefix(info.UpstreamModelName, "o") {
@@ -326,8 +327,8 @@ func (a *Adaptor) ConvertOpenAIRequest(c *gin.Context, info *relaycommon.RelayIn
 		// gpt-5系列模型适配 归零不再支持的参数
 		if strings.HasPrefix(info.UpstreamModelName, "gpt-5") {
 			request.Temperature = nil
-			request.TopP = 0 // oai 的 top_p 默认值是 1.0，但是为了 omitempty 属性直接不传，这里显式设置为 0
-			request.LogProbs = false
+			request.TopP = nil
+			request.LogProbs = nil
 		}
 
 		// 转换模型推理力度后缀