🐛 fix(mistral): validate and generate new IDs for tool calls and tool call IDs;…

🐛 fix(mistral): validate and generate new IDs for tool calls and tool call IDs; Correctly handle null content for assistant messages with tool_calls.

relay/channel/mistral/text.go

 package mistral
 
 import (
+	"one-api/common"
 	"one-api/dto"
+	"regexp"
 )
 
+var mistralToolCallIdRegexp = regexp.MustCompile("^[a-zA-Z0-9]{9}$")
+
 func requestOpenAI2Mistral(request *dto.GeneralOpenAIRequest) *dto.GeneralOpenAIRequest {
 	messages := make([]dto.Message, 0, len(request.Messages))
+	idMap := make(map[string]string)
 	for _, message := range request.Messages {
+		// 1. tool_calls.id
+		toolCalls := message.ParseToolCalls()
+		if toolCalls != nil {
+			for i := range toolCalls {
+				if !mistralToolCallIdRegexp.MatchString(toolCalls[i].ID) {
+					if newId, ok := idMap[toolCalls[i].ID]; ok {
+						toolCalls[i].ID = newId
+					} else {
+						newId, err := common.GenerateRandomCharsKey(9)
+						if err == nil {
+							idMap[toolCalls[i].ID] = newId
+							toolCalls[i].ID = newId
+						}
+					}
+				}
+			}
+			message.SetToolCalls(toolCalls)
+		}
+
+		// 2. tool_call_id
+		if message.ToolCallId != "" {
+			if newId, ok := idMap[message.ToolCallId]; ok {
+				message.ToolCallId = newId
+			} else {
+				if !mistralToolCallIdRegexp.MatchString(message.ToolCallId) {
+					newId, err := common.GenerateRandomCharsKey(9)
+					if err == nil {
+						idMap[message.ToolCallId] = newId
+						message.ToolCallId = newId
+					}
+				}
+			}
+		}
+
 		mediaMessages := message.ParseContent()
+		if message.Role == "assistant" && message.ToolCalls != nil && string(message.Content) == "null" {
+			mediaMessages = []dto.MediaContent{}
+		}
 		for j, mediaMessage := range mediaMessages {
 			if mediaMessage.Type == dto.ContentTypeImageURL {
 				imageUrl := mediaMessage.GetImageMedia()