Add i18n support with react-i18next

[Geczy]

Implements internationalization support across the application using react-i18next.

• Adds dependencies: Includes react-i18next and i18next in package.json to enable internationalization support.
• Initializes i18next: Modifies _app.tsx to initialize i18next with a basic configuration and wraps the application in the <I18nextProvider> component for language translation context.
• Updates JSON translations: Enhances public/locales/en/common.json with new keys and default English translations for various components, ensuring all static text across the application is ready for translation.
• Integrates translation hooks: Updates several components (Hero.tsx, advanced.tsx, chat.tsx, index.tsx, overlay.tsx, and dashboard/index.tsx) to use the t function from react-i18next for dynamically translating static text.
• Ensures dynamic content translation: Ensures that dynamic content, such as titles and subtitles in dashboard features and setup steps, is also translated according to the current language setting.

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