delete mock data and replace it with Indisponible for Null and Undefined values

Main changes:

• Removal of showMockData and LOADING_TIMEOUT: no more timeout logic or mock data.
• Removal of useEffect: no more timeout management.
• Helper function getValueOrUnavailable: returns "Unavailable" if the value is null, undefined, or empty.
• Helper functions getFirstName and getLastName: extract first/last name from driverName and return "Unavailable" if absent.
• Display during loading: spinner only if isLoading && !data; otherwise, display fields with empty values ​​or "Unavailable" depending on the received data.