Iinitial version of Authly framework

• Introduce core authentication & authorization features built on FastAPI.
• Implement JWT-based access/refresh token generation, validation, and secure invalidation.
• Add secure secrets management with key rotation, backups, and secure deletion.
• Provide user management endpoints (CRUD) integrated with PostgreSQL via psycopg_pool.
• Integrate rate limiting and login attempt tracking for enhanced security.
• Set up project configuration with Poetry, environment examples, Docker DB initialization scripts, and extensive test coverage.