“Song of Everlasting Regret” draws on a well-known Chinese narrative of love, power, and remembrance, a story that has traveled for centuries through poetry, opera, and later film. At National Sawdust in Brooklyn, composer Huang Ruo appears alongside soprano Kelly Clarke and pianist Joanne Kang, with the program also including the NYC premiere of Huang Ruo’s “A DUST IN TIME.” Heard in a contemporary classical setting, the material becomes less pageant than reckoning, tracing how private grief is shaped by public history. One clear effect is how the music treats memory as something unstable rather than consoling.