For the gastrique sauce: Combine the orange juice, sugar, garlic, orange liqueur, ginger and 2 cups of the vinegar in a medium saucepan and bring to a boil over high heat. Cook until the mixture reduces by half, about 20 minutes. Remove 1 cup of the reduction and set aside for the candied kumquats.
Strain the remainder of the reduction left in the saucepan and transfer to a large high-sided saute pan. Cook over high heat until reduced by half again, about 15 minutes. Make small slits in the habanero with a paring knife, add it to the reduction and let cook for 5 minutes more. Add the remaining 2 tablespoons vinegar and cook for 1 minute. Whisk in the butter and cook until it melts. Add the parsley, chives, peppercorns and thyme and season with salt and pepper.
For the duck confit: Whisk together the cinnamon, chile powders, cumin, coriander, ginger, sugar, garlic powder, onion powder, salt, allspice, cloves, fennel seed, cayenne, chile de arbol and 2 tablespoons of the black pepper in a small bowl and set aside.
Heat the oil in a large nonstick pan over medium heat, add the bacon and cook until lightly golden brown on both sides and the fat has rendered, about 10 minutes. Remove the bacon to a plate lined with paper towels.
Preheat the oven to 350 degrees and place a baking rack on a rimmed baking sheet.
Season the duck legs with salt, pepper and some of the spice rub. Store any remaining spice rub in an airtight container for a later use. Place the legs fat-side down in the baking drippings in the nonstick pan. Cook slowly over medium heat until the skin is very crisp, about 10 minutes. Turn them over and cook until the other side is crisp, 10 minutes more. Transfer the prepared baking sheet and keep warm in theoven until ready to serve.
For the duck breasts: Season the duck breasts on both sides with salt and pepper and place skin-side down in a cast iron pan. Cook slowly over medium heat, draining the rendered fat from the pan a few times, until the skin is very crisp, about 25 minutes. Turn the breasts over and continue cooking to medium and an instant-read thermometer inserted into the center registers 140 degrees F. Remove to a cutting board and let rest for 10 minutes before slicing crosswise into 1/4-inch-thick slices.
For the candied kumquats: Bring the reserved 1 cup gastrique to a boil in a small saucepan, reduce the heat to low, add the kumquarts and cook until soft and candied, about 20 minutes.
For the cranberry relish: Combine the orange juice and honey in a small saute pan, bring to a boil and cook until reduced by a quarter, about 3 minutes. Add the cranberries and cook until they pop and the mixture thickens slightly, about 10 minutes more. Set aside until ready to serve.
To serve: Spoon some of the gastrique onto 4 large dinner plates. Top with the duck confit and the sliced duck and spoon some of the cranberries and kumquarts on the sides. Garnish with thyme sprigs, if desired.