Cover the rice stick noodles with warm water in a large bowl until pliable but still a bit firm in the core, 20β30 minutes; drain well.
In a small saucepan over low heat, combine the palm sugar, fish sauce, tamarind concentrate, and 0.25 cup of the water; stir until the sugar dissolves and the sauce is glossy, 2β3 minutes. Reserve the remaining 0.25 cup water to splash in if the noodles look dry later.
Heat a wok (or large skillet) over medium-high until lightly smoking, about 2 minutes, then add the neutral oil and swirl to coat.
Add the garlic, shallot, sweet salted preserved radish, and dried shrimp; stir-fry until fragrant and just starting to color, 30β45 seconds.
Add the firm tofu and shrimp; stir-fry until the tofu edges turn golden and the shrimp are pink and nearly cooked through, 2β3 minutes.
Push everything to one side of the wok, crack in the eggs, and scramble until just set, 30β45 seconds, then fold into the mixture.
Add the drained noodles and immediately pour in the sauce; toss continuously until the noodles are tender but springy and evenly coated, 2β4 minutes, adding splashes of the reserved water as needed to loosen.
Sprinkle in the Thai chili flakes, then add the bean sprouts and garlic chives; toss just until the sprouts are heated through and the chives wilt slightly, 30β60 seconds.
Remove from heat, plate, and top with the roasted peanuts. Serve hot with the lime wedges; diners can squeeze to taste.