Set up the foundational files and configurations for the Hygiéniste Pro AI application. This includes:
- Initializing `package.json` with necessary dependencies (React, Vite, Gemini SDK, Tailwind CSS).
- Configuring Vite for development and building.
- Setting up `tsconfig.json` for TypeScript.
- Creating basic `index.html` and `src/main.tsx` for React app entry point.
- Adding `.gitignore` to manage project files.
- Defining app metadata (`metadata.json`) including microphone permissions.
- Updating `README.md` with instructions for local execution and deployment.
- Adding `.env.example` for API key configuration.
- Implementing core UI and audio handling logic in `src/App.tsx` and styling in `src/index.css`.
