Preheat oven to 350°F.
In a small bowl, combine 1 Tbs. plus 1 teaspoon salt, 2 tsp. black pepper, curry powder, cumin, ground allspice berries, cardamom, and turmeric. Place lamb shanks on a plate or baking sheet and sprinkle with spice mix, rubbing with your hands to distribute and coat. Cover and place in refrigerator. Let marinate at least 1 hour and up to 2 days in advance.
Heat a large dutch oven with a tight fitting lid over medium-high heat. Add 2 Tbs. olive oil, swirl to coat, and add lamb shanks. Sear on all sides, in batches if necessary so as not to overcrowd pan, until deeply golden, 5 to 6 minutes per side, about 18 minutes total. Replenish oil between batches as necessary and adjust heat to prevent over-browning.
Remove shanks to a plate and add additional 1 Tbs. olive oil if pan is dry. Add carrots, onion, garlic, and habanero. Season with salt and pepper and sauté stirring occasionally, until vegetables are softened and beginning to turn golden on the edges, about 8 minutes. Add red wine, port, chicken stock, thyme, bay leaf, and cloves, scraping to deglaze and incorporate any brown bits from bottom of pan. Return shanks to pot, nestling them into liquid in as even a layer as possible. Liquid should come nearly to the top of the shanks. If necessary, add water to reach appropriate level. Cover pot and transfer to oven. Braise, basting top of shanks with liquid every 45 minutes, until meat is tender and falling off the bone, about 3 to 3 ½ hours.
Remove shanks from pot and cover to keep warm. If desired, return pot to stovetop and reduce sauce over medium-high heat until reduced to desired consistency. Season to taste sauce and meat with additional salt and pepper.
Divide shanks among shallow serving bowls. Surround with braised vegetables and pan sauce. Serve immediately, topped with cilantro, parsley, and chives.
