Description: - Create state that determines which country is currently displayed. Tasks: - Create state for the active index or country ID. - Display the correct country in the country card. - Ensure the index remains valid when the selection changes. - Select the first available country by default. Acceptance Criteria: - The application displays one active country. - State updates refresh the country card. - An invalid index or an empty selection does not cause the application to crash. - The first available country is displayed by default.