fix: changeoptional field to pointer type (#1907)

* fix:修复在渠道配置中设置模型重定向时，temperature为0被忽略的问题

* fix: set optional fields to pointer type

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Co-authored-by: JustSong <songquanpeng@foxmail.com>

relay/adaptor/cloudflare/model.go

@@ -9,5 +9,5 @@ type Request struct {
 	Prompt      string          `json:"prompt,omitempty"`
 	Raw         bool            `json:"raw,omitempty"`
 	Stream      bool            `json:"stream,omitempty"`
-	Temperature float64         `json:"temperature,omitempty"`
+	Temperature *float64        `json:"temperature,omitempty"`
 }