Remove unnecessary `pathlib.Path` conversions. (CACHE_DIR and DATA_DIR)
Use `/` Path joining shorthand to ensure using platform specific Path separators (Windows: \\, Unix: /)
Use `logging.getLevelNamesMapping()` for getting all valid logging levels. This also allows adding new ones using `logging.addLevel()`. This feature was [added](https://docs.python.org/3.11/library/logging.html#logging.getLevelNamesMapping) in Python 3.11 which is above the minimum supported Python version for open-webui.
tidely