Whisk soy sauce, vinegar, sesame seeds and chile-garlic sauce in a large bowl; place near the stove. Place a large carbon-steel wok or large skillet over high heat until very hot. Swirl in oil and add snap peas and tomatoes. Sprinkle with salt and stir-fry until the peas are tender-crisp and the tomatoes are softened, 4 to 5 minutes. Transfer to the bowl with the soy sauce mixture; toss to combine.