Annie Clark has always betrayed a commanding dose of swagger alongside her pomp, preciousness and finely crafted femininity. Her band St. Vincent’s music sounds as luxurious and pretty as her vintage wardrobe, but there’s a fiery-smart borderline head case inhabiting it. The aggression comes to the fore even more in concerts, where she flaunts her guitar-goddess aptitude in a manner best described as downright nasty. Still, the full-fledged violence of her Record Store Day single “Krokodil” came as a shock. If Clark usually makes chamber pop, this unhinged blast of industrial hostility burns that chamber down. The same fate might befall the Newport this Tuesday when St. Vincent plays after baroque Texas indie-rockers Shearwater.