refactor: replace Kokoro-82M with suno/bark for TTS, update HF cache path, and add model warmup on startup.

backend/tests/test_tts_asr_unit.py

@@ -16,8 +16,9 @@ from unittest.mock import Mock, MagicMock, patch
 import tempfile
 import numpy as np
 
-# 确保可以导入tts_asr模块
-sys.path.insert(0, os.path.join(os.path.dirname(__file__), '..'))
+# 确保可以导入backend和tts_asr模块
+sys.path.insert(0, os.path.abspath(os.path.join(os.path.dirname(__file__), '../..')))
+sys.path.insert(0, os.path.abspath(os.path.join(os.path.dirname(__file__), '..')))
 
 
 class TestAppleSiliconDetection(unittest.TestCase):
@@ -174,7 +175,7 @@ class TestModelSizeSelection(unittest.TestCase):
             import backend.tts_asr as tts_asr_module
             importlib.reload(tts_asr_module)
             
-            from backend.tts_asr import _get_recommended_model_size
+            from backend.tts_asr import _get_recommended_model_size, WHISPER_MODEL_SIZES
             # 应该回退到推荐大小而不崩溃
             size = _get_recommended_model_size()
             self.assertIn(size, WHISPER_MODEL_SIZES.keys())
@@ -299,8 +300,8 @@ class TestModelCacheCheck(unittest.TestCase):
         """测试离线模式下缺失模型的处理"""
         from backend.tts_asr import _check_model_cached
         
-        # 模拟transformers缓存路径
-        with patch('transformers.file_utils.default_cache_path', '/nonexistent/path'):
+        # 模拟缓存路径
+        with patch('huggingface_hub.constants.HF_HUB_CACHE', '/nonexistent/path'):
             result = _check_model_cached('nonexistent/model')
             # 应该返回False（模型未缓存）
             self.assertFalse(result)