feat: 更新配置文档

backend/internal/orchestrator/pipeline.go

@@ -22,6 +22,7 @@ type Pipeline struct {
 	llmService llm.Service
 	ttsService tts.Service
 	sessionMgr session.Manager
+	model      string // LLM 模型名，用于 llm_done 上报
 }
 
 // New 创建 Pipeline 实例。
@@ -30,12 +31,14 @@ func New(
 	llmService llm.Service,
 	ttsService tts.Service,
 	sessionMgr session.Manager,
+	model string,
 ) *Pipeline {
 	return &Pipeline{
 		sttService: sttService,
 		llmService: llmService,
 		ttsService: ttsService,
 		sessionMgr: sessionMgr,
+		model:      model,
 	}
 }
 
@@ -206,7 +209,7 @@ func (p *Pipeline) ProcessQuery(
 		Type:      "llm_done",
 		RequestID: req.RequestID,
 		FullText:  fullText,
-		Model:     "gpt-4o",
+		Model:     p.model,
 		LatencyMs: latency,
 	}); err != nil {
 		log.Errorw("发送 llm_done 失败", "error", err)