refactor(api): Code optimization based on review comments.

- Removed authentication dependency for the health check endpoint in lightrag_server.py
- Removed the authentication dependency for the entire router in ollama_api.py
- Updated the parameter list and example usage in README.md, removing authentication-related parts
- Removed neo4j and tqdm dependencies from requirements.txt
- Deleted command-line argument parsing code related to authentication from utils_api.py

lightrag/api/requirements.txt

@@ -8,14 +8,12 @@ python-multipart
 tenacity
 tiktoken
 uvicorn
-tqdm
 jiter
 httpcore
 distro
 httpx
 openai
 asyncpg
-neo4j
 pytz
 python-jose[cryptography]
 passlib[bcrypt]