refactor(engine): 修改虚拟环境设置，修改音频工具函数

- 更新虚拟环境目录名为 .venv
- 调整音频块采集速率默认值为 10
- 为 AudioStream 类添加重设音频块大小的方法
- 更新依赖文件 requirements.txt

engine/main.spec

@@ -4,9 +4,9 @@ from pathlib import Path
 import sys
 
 if sys.platform == 'win32':
-    vosk_path = str(Path('./subenv/Lib/site-packages/vosk').resolve())
+    vosk_path = str(Path('./.venv/Lib/site-packages/vosk').resolve())
 else:
-    vosk_path = str(Path('./subenv/lib/python3.12/site-packages/vosk').resolve())
+    vosk_path = str(Path('./.venv/lib/python3.12/site-packages/vosk').resolve())
 
 a = Analysis(
     ['main.py'],