Hope it is a nest. It’s a good idea to put some long grasses out near the leaves. I had a hoglet here who didn’t hibernate and he made a nest in a box I normally use for feeding. Mostly filmed on video – the cam was right opposite. I had some long ornamental grasses and I cut some of them and left them behind the box. He took them in and they were all woven in amongst the leaves. They helped to keep it all together and the right shape.
He didn’t use the nest full time, but as a place to go and shelter in the warm between snacks on the cold winter evenings.