Lay the almonds on a sheet pan and toast them until they start to crack. Watch them closely: About 9 minutes in, I usually bite into one to see if it’s no longer white on the inside. When toasted, remove from the oven and let cool to room temperature, then crush in a mortar and pestle or coarsely chop.
Slice the cabbage on a mandoline into a large bowl. Sprinkle on 1 teaspoon of the fine sea salt and mix by hand well, massaging the salt into the cabbage. Next, prepare the beets, celery root, and carrots by slicing them thinly on a mandoline and then slicing the pieces into thin julienned strips. Mix each vegetable into the cabbage as you finish slicing it, tossing and squeezing with your hands to combine and distribute the salt. When the vegetable mixture has sat for 30 minutes to 1 hour, place in a colander and rinse quickly. Then lay the vegetables on a clean kitchen towel (not your fanciest one: the beets may leak a little color onto them) and blot well (maybe using a second towel to really get the moisture off).
In a small bowl, make the dressing by whisking together the lime zest and juice, yogurt, olive oil, garlic, za’atar, and remaining 1 teaspoon fine sea salt. Season well with pepper. Taste and adjust the salt if necessary.
Transfer the vegetables to a large bowl and fold in the yogurt dressing and most of the almonds, sesame seeds, dill, and mint, reserving some for the top of the salad. Pile the salad onto a serving platter or bowl and scatter the remaining sesame seeds, almonds, and herbs over the top. Drizzle with some olive oil and sprinkle with flaky salt.