Recently (last week) we discovered a bunch of small, dark brown stuff in the cabinet under the sink. At first I thought they were coffee grounds (we keep the compost bucket under the sink, emptied daily) and cleaned them up. But they returned, and we discovered them on the shelves as well as the floor of the cabinet. Picture attached. Are these bug sacks/eggs? And if so, should we put them outside or trash them (invasives)? They have a rather hard exterior, but can be broken open with a strong thumbnail, and reveal a reddish interior. They all seem to have a tiny "tail" on one end. Not at all sure how they arrived (much less what they are).