Update authentication credentials in .env.example and modify password verification in auth.py to enhance security. The default password has been changed to 'volaris123' for improved security practices.

Update .gitignore to include frontend and Lung Cancer Guidelines directories. Enhance CORS middleware configuration to allow origins from environment variables, with defaults for local development. Modify session cookie settings to require secure flag for SameSite=None, improving security for cross-site requests.

Enhance API security and functionality by adding authentication middleware and session management. Updated app.py to include the new auth router and integrated authentication checks for protected endpoints. Modified requirements.txt to include necessary libraries for session handling. Updated .env.example to include authentication credentials. Improved retrieval functions with query expansion for better medical term matching and enriched context in responses.