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/lightrag_server.py

@@ -400,7 +400,7 @@ def create_app(args):
             "token_type": "bearer"
         }
 
-    @app.get("/health", dependencies=[Depends(optional_api_key), Depends(get_auth_dependency())])
+    @app.get("/health", dependencies=[Depends(optional_api_key)])
     async def get_status():
         """Get current system status"""
         # Get update flags status for all namespaces