Preheat oven to 375 degrees. Bake bread on a baking sheet until dry and edges are golden, about 10 minutes. Transfer to a bowl.
Place turkey, skinned-side down, on a cutting board. Slice through thickest part of breast, creating a flap. Cover with plastic wrap. With a mallet, pound to an even thickness (about 3/4 inch). Remove plastic, season with salt and pepper, and store in refrigerator up to 1 day.
Heat butter in a skillet over medium-high heat until foamy. Add onion, celery, garlic, herbs, and 1/2 teaspoon salt. Cook until onion is translucent, about 4 minutes. Transfer to bowl with bread; add broth, cranberries, and pistachios. Stir to combine. Season with salt and pepper.
Place turkey, skinned-side down, on a work surface. Season with salt and pepper. Spread stuffing over top, leaving a 1/2-inch border. Working from one short side, roll breast up tightly into a log, enclosing stuffing. Turn seam-side down. Drape bacon slices over breast, overlapping slightly to cover completely. With kitchen twine, tie at 4 even intervals; replace any stuffing that falls out.
Roast until a thermometer inserted in thickest part reads 155 degrees (temperature will continue to rise during resting), about 1 hour, 10 minutes. Let rest 15 minutes before slicing and serving.