chore: rewrite 429 prompt text (close #96)

controller/relay.go

@@ -75,6 +75,9 @@ func countToken(text string) int {
 func Relay(c *gin.Context) {
 	err := relayHelper(c)
 	if err != nil {
+		if err.StatusCode == http.StatusTooManyRequests {
+			err.OpenAIError.Message = "负载已满，请稍后再试，或升级账户以提升服务质量。"
+		}
 		c.JSON(err.StatusCode, gin.H{
 			"error": err.OpenAIError,
 		})