feat: Add grammar diagnosis and TTS support

feat: Improve UI and UX with theme and font updates

fix: Remove outdated message in initial AI prompt

feat: Refactor state management and remove unused variables

fix: Simplify offline handling and remove difficulty state

feat: Add suggestion model and improve translation logic

fix(network): Improve network error handling and API key fallback

feat: Add network status and reconnection logic

feat(suggestions): Improve suggestion generation context

feat(global): Define aistudio global variable

feat: Define AIStudio interface for window object

feat: Rename app and update styles

feat: Initialize LingoLink project with Vite and React

Initial commit