fix: pipeline.go TTS 输出格式/采样率从配置读取

- New() 改为接收 *config.Config 参数
- OutputFmt/SampleRate 从 config.AI.TTS 读取

backend/internal/orchestrator/pipeline.go

@@ -11,6 +11,7 @@ import (
 	"github.com/hhs/camtalk/internal/ai/llm"
 	"github.com/hhs/camtalk/internal/ai/stt"
 	"github.com/hhs/camtalk/internal/ai/tts"
+	"github.com/hhs/camtalk/internal/config"
 	"github.com/hhs/camtalk/internal/logger"
 	"github.com/hhs/camtalk/internal/models"
 	"github.com/hhs/camtalk/internal/session"
@@ -25,6 +26,8 @@ type Pipeline struct {
 	model       string // LLM 模型名，用于 llm_done 上报
 	ttsVoice    string // TTS 音色
 	ttsSpeed    float64 // TTS 语速
+	ttsOutputFmt string // TTS 输出格式
+	ttsSampleRate int   // TTS 输出采样率
 }
 
 // New 创建 Pipeline 实例。
@@ -33,18 +36,18 @@ func New(
 	llmService llm.Service,
 	ttsService tts.Service,
 	sessionMgr session.Manager,
-	model string,
+	cfg *config.Config,
-	ttsVoice string,
-	ttsSpeed float64,
 ) *Pipeline {
 	return &Pipeline{
 		sttService:    sttService,
 		llmService:    llmService,
 		ttsService:    ttsService,
 		sessionMgr:    sessionMgr,
-		model:      model,
+		model:         cfg.AI.LLM.Model,
-		ttsVoice:   ttsVoice,
+		ttsVoice:      cfg.AI.TTS.Voice,
-		ttsSpeed:   ttsSpeed,
+		ttsSpeed:      cfg.AI.TTS.Speed,
+		ttsOutputFmt:  cfg.AI.TTS.OutputFormat,
+		ttsSampleRate: cfg.AI.TTS.SampleRate,
 	}
 }
 
@@ -314,8 +317,8 @@ func (p *Pipeline) synthesizeTTS(
 	ttsStream, err := p.ttsService.SynthesizeStream(ctx, sentenceCh, tts.Options{
 		Voice:      p.ttsVoice,
 		Speed:      p.ttsSpeed,
-		OutputFmt:  "mp3",
+		OutputFmt:  p.ttsOutputFmt,
-		SampleRate: 24000,
+		SampleRate: p.ttsSampleRate,
 	})
 	if err != nil {
 		log.Errorw("TTS 合成启动失败", "error", err)