🐛 fix(utils.py): rename `cache_class` variable to `cache_type` for clarity and consistency

🔧 chore(utils.py): refactor `setup_llm_caching` to extract cache setup logic into a separate function for better modularity and readability
The variable `cache_class` has been renamed to `cache_type` to improve clarity and consistency with the naming conventions. The `setup_llm_caching` function has been refactored to extract the cache setup logic into a separate function called `set_langchain_cache`. This improves modularity and readability of the code.