Whisk 3 tablespoons black vinegar, 2 heaped tablespoons sugar, 1 teaspoon dark soy sauce, 1 tablespoon light soy sauce, a pinch of salt, 1/2 cup water, and 1/2 tablespoon potato starch until the sugar and starch fully dissolve.
Toss the cubed chicken thigh with the minced scallion whites, ginger, Shaoxing wine, light soy sauce, oyster sauce, and cornstarch, mix until every piece is coated, then drizzle 1 tablespoon oil over the top, cover, and marinate 15 minutes.
Heat a wok over high heat, add 1 tablespoon oil, and slide in the chicken in a single layer.
Stir fry the chicken 3 to 4 minutes until golden at the edges and cooked through, then scoop it out with a slotted spoon and set aside.
Add another tablespoon of oil to the wok, sear the shrimp 1 to 2 minutes per side until they curl and turn opaque, then remove them and set aside with the chicken.
Add the last tablespoon of oil, then the scallion segments, sliced garlic, and dried chilies, and stir fry 30 seconds until fragrant and the chilies darken slightly.
Slide the chicken, shrimp, and roasted peanuts back into the wok and toss everything together over high heat.
Pour in the sauce, stir fry 30 to 45 seconds until it thickens into a glossy coat, then finish with 1 tablespoon chili oil, toss once more, and turn off the heat.
Scrape everything onto a warm platter, spoon the pan sauce over the top, and serve immediately with steamed rice.