Fix Improper Error Handling in Micronaut

@Controller("/users")
public class UserController {
    @Get("/{id}")
    public HttpResponse getUser(String id) {
        try {
            // Business logic that might fail
            throw new SQLException("Connection refused to 10.0.5.21:5432");
        } catch (Exception e) {
            // VULNERABLE: Directly returning the exception object or its message
            // leaks internal infrastructure details and stack traces to the client.
            return HttpResponse.serverError(e);
        }
    }
}

@Produces
@Singleton
@Requires(classes = {Throwable.class, ExceptionHandler.class})
public class GlobalExceptionHandler implements ExceptionHandler> {
private static final Logger LOG = LoggerFactory.getLogger(GlobalExceptionHandler.class);

@Override
public HttpResponse<?> handle(HttpRequest request, Throwable exception) {
    String errorId = java.util.UUID.randomUUID().toString();
    
    // Log the full stack trace internally for debugging
    LOG.error("Unhandled Exception [ID: {}]: {}", errorId, exception.getMessage(), exception);

    // Return a sanitized response to the client
    return HttpResponse.serverError(Map.of(
        "status", "error",
        "message", "An internal error occurred. Contact support with the reference ID.",
        "ref_id", errorId
    ));
}
}