For steak, stir together salt, pepper, harissa, and garlic powder in a small bowl. Drizzle steaks with olive oil on all sides and then season well with the steak rub. Set aside. Preheat grill to medium-high heat.
Grill steaks over medium-high heat for 5-6 minutes per side, depending on thickness. Use a meat thermometer to check doneness. Steaks should reach an internal temperature of 145˚F for medium rare. Let steaks rest for 5 minutes before slicing thin.
For yogurt sauce, peel and grate half of a large cucumber (remove seeds as well). Place grated cucumber in a few paper towels and remove as much water as possible. Stir together yogurt, strained cucumber, garlic, olive oil, lemon juice, and a pinch of salt.
Preheat toppings for the wraps by slicing vegetables thinly and crumbling feta.
Make a wrap by warming a naan or flatbread on the grill. Add a layer of yogurt sauce, then lettuce and veggies and top with sliced steak, crumbled egg, chimichurri sauce, and fresh mint.
Wrap tightly and serve wraps immediately while warm.