Refactor text chunking implementation and update configuration

- Moved SentenceTextChunker and SentenceTextChunkerConfig to the utils module for better organization.
- Updated pytest.ini to include the current directory in the Python path.
- Added a new utils module with shared utility helpers.
- Adjusted import paths in the test files to reflect the new location of text chunking classes.

src/api/endpoints.py

@@ -7,7 +7,7 @@ from fastgpt_client.exceptions import (
 )
 from ..core.fastgpt_client import get_fastgpt_client
 from ..core.config import Config
-from ..voice.text_chunker import SentenceTextChunker, SentenceTextChunkerConfig
+from ..utils.text_chunker import SentenceTextChunker, SentenceTextChunkerConfig
 from loguru import logger
 import json
 import re