feat: update i18n configuration to prioritize browser language; enhance language detection
feat: add new translation keys for form submission feedback in English and German
- Added backend package.json with dependencies for Express, MySQL, and EJS.
- Created server.js for backend server setup with basic routing and error handling.
- Added EJS view for the index page.
- Set up Docker Compose configuration for frontend, backend, and MySQL database services.
- Created Dockerfile for frontend build process using Node and Nginx.
- Configured Nginx for serving frontend application.
- Implemented i18n setup for internationalization with English and German language support.
- Added localization files for English and German languages.
