feat: support multipart/form-data format request (#1690)

* "add parser multipart/form-data"

* chore: fix impl

* chore: update impl

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

middleware/distributor.go

@@ -12,7 +12,7 @@ import (
 )
 
 type ModelRequest struct {
-	Model string `json:"model"`
+	Model string `json:"model" form:"model"`
 }
 
 func Distribute() func(c *gin.Context) {