public function boot()
{
    Route::macro('preserveQueryParams', function () {
        $this->middleware(function ($request, $next) {
            if ($request->route()->getAction('preserveQuery')) {
                session(['previous_params' => $request->query()]);
            }
            return $next($request);
        });
        return $this;
    });
    
    // ...existing code...
}