Allium and muscari are both fully hardy in the Northeast. Do not dig them up and bring them indoors since that would not only be extra work for you, but would also result in weaker plants. Hardy bulbs grow root systems that remain in place over the winter and are there to provide nutrients and water to the plants right away in the spring. Since they have their roots in place, the bulbs can use all of their stored energy in making flower stalks and leaves. If a bulb is put into the ground in the spring, however, it must use some of its energy to first make roots before it can grow the flowers and leaves. That’s why hardy bulbs are planted in the fall, so that they can grow roots in the fall that will sustain the plants quicker in the coming growing season.
Be sure to scatter an organic fertilizer over the ground in the area where your bulbs are planted. This is far better than just dumping some fertilizer in the bottom of the planting hole. Keeping the area fertile means that those nutrients will be available to the plants even when their roots grow beyond the planting hole. You don’t have to work the fertilizer in, but if you’ve scattered the fertilizer before planting some of it will naturally get incorporated into the soil when you dig the holes and plant the bulbs.