optimize: MJ 部分调整、优化

MJ
增加simple-change、list接口，
变换和重试操作区别出来，价格与绘图一样
优化图片返回

common/model-ratio.go

@@ -14,7 +14,7 @@ import (
 // 1 === $0.002 / 1K tokens
 // 1 === ￥0.014 / 1k tokens
 var ModelRatio = map[string]float64{
-	"midjourney":                50,
+	//"midjourney":                50,
 	"gpt-4-gizmo-*":             15,
 	"gpt-4":                     15,
 	"gpt-4-0314":                15,
@@ -80,6 +80,12 @@ var ModelRatio = map[string]float64{
 
 var ModelPrice = map[string]float64{
 	"gpt-4-gizmo-*": 0.1,
+	"mj_imagine":    0.1,
+	"mj_variation":  0.1,
+	"mj_reroll":     0.1,
+	"mj_blend":      0.1,
+	"mj_describe":   0.05,
+	"mj_upscale":    0.05,
 }
 
 func ModelPrice2JSONString() string {