refactor: MiMo TTS 使用 trace.FromContext 支持追踪

backend/internal/ai/tts/mimo.go

@@ -11,6 +11,7 @@ import (
 	"strings"
 	"time"
 
+	"github.com/hhs/camtalk/internal/trace"
 	"github.com/hhs/camtalk/internal/util"
 	"go.uber.org/zap"
 )
@@ -109,7 +110,8 @@ func (m *MiMoService) SynthesizeStream(ctx context.Context, textStream <-chan st
 
 			audio, err := m.synthesize(ctx, text, voice)
 			if err != nil {
-				m.logger.Warnw("mimo tts: synthesize failed",
+				log := trace.FromContext(ctx)
+				log.Warnw("mimo tts: synthesize failed",
 					"error", err,
 					"text_len", len(text),
 					"text_preview", util.Truncate(text, 100))