Expanded documentation to cover the new downloads manager, native context menu, OAuth/SSO and WebAuthn compatibility, and user agent strategy. Updated project structure and core concepts to reflect these features and clarified session and popup handling for authentication. Fixed minor typos and improved feature descriptions for clarity.
Added detailed documentation files for code of conduct, contributing guidelines, core concepts, features, and project structure in the documentation/ directory. Updated README.md to reference new documentation, expand feature descriptions, and clarify setup instructions.
andrew