[结束提示音优化]：完成Codex通知音资产内置，包含音频提取、配置默认值和回归测试

tests/test_pipeline_llm_tts.py

@@ -12,7 +12,7 @@ from owner_voice_pet.models import AudioFrame, ErrorCode, Message, PipelineState
 from owner_voice_pet.pipeline import VoicePipeline
 from owner_voice_pet.stt import MetadataSttProvider
 from owner_voice_pet.transport import MemoryAudioTransport
-from owner_voice_pet.tts import CloudTtsProvider, SentenceBuffer, SineTtsProvider, make_prompt_chime, sanitize_tts_text
+from owner_voice_pet.tts import CloudTtsProvider, SentenceBuffer, SineTtsProvider, make_end_chime, make_prompt_chime, sanitize_tts_text
 from owner_voice_pet.vad import EnergyVadProvider, VadRecorder
 from owner_voice_pet.wakeword import KeywordWakeWordProvider
 
@@ -78,8 +78,24 @@ class PipelineLlmTtsTests(unittest.TestCase):
 
         self.assertEqual(segment.duration_ms, 140)
         self.assertEqual(segment.metadata["chime"], "end")
+        self.assertEqual(segment.metadata["source"], "synthetic")
         self.assertGreater(len(segment.pcm), 0)
 
+    def test_end_chime_uses_file_when_present(self) -> None:
+        segment = make_end_chime(file_path="assets/sounds/codex-notification.wav")
+
+        self.assertEqual(segment.metadata["source"], "file")
+        self.assertEqual(segment.metadata["path"], "assets/sounds/codex-notification.wav")
+        self.assertEqual(segment.metadata["format"], "wav")
+        self.assertGreater(segment.duration_ms, 0)
+
+    def test_end_chime_falls_back_to_synthetic_when_file_missing(self) -> None:
+        segment = make_end_chime(file_path="/tmp/owner-voice-pet-missing-chime.wav", duration_ms=140)
+
+        self.assertEqual(segment.metadata["source"], "synthetic")
+        self.assertEqual(segment.metadata["chime"], "end")
+        self.assertEqual(segment.duration_ms, 140)
+
     def test_cloud_tts_posts_speech_request(self) -> None:
         class FakeResponse:
             def __enter__(self):