feat: 更新配置文档

backend/internal/ai/tts/openai.go

@@ -15,6 +15,7 @@ import (
 // OpenAIService 基于 OpenAI TTS API 的语音合成实现。
 type OpenAIService struct {
 	apiKey   string
+	model    string
 	voice    string
 	speed    float64
 	endpoint string
@@ -24,7 +25,10 @@ type OpenAIService struct {
 }
 
 // NewOpenAIService 创建 OpenAI TTS 服务。
-func NewOpenAIService(apiKey, voice, endpoint string, speed float64, timeoutSec int, logger *zap.SugaredLogger) *OpenAIService {
+func NewOpenAIService(apiKey, model, voice, endpoint string, speed float64, timeoutSec int, logger *zap.SugaredLogger) *OpenAIService {
+	if model == "" {
+		model = "tts-1"
+	}
 	if voice == "" {
 		voice = "alloy"
 	}
@@ -40,6 +44,7 @@ func NewOpenAIService(apiKey, voice, endpoint string, speed float64, timeoutSec
 	}
 	return &OpenAIService{
 		apiKey:   apiKey,
+		model:    model,
 		voice:    voice,
 		speed:    speed,
 		endpoint: endpoint,
@@ -109,7 +114,7 @@ func (o *OpenAIService) synthesize(ctx context.Context, text, voice string, spee
 	defer cancel()
 
 	body := ttsRequest{
-		Model:          "tts-1",
+		Model:          o.model,
 		Input:          text,
 		Voice:          voice,
 		ResponseFormat: "mp3",