Export via realtime capture (offline render is realtime here & looked frozen)

@csound/browser's worklet only performs at real time (perform() without start() no-ops; with start() it conflicts/hangs) — so offline render of a long song ran for minutes with no feedback and read as frozen/stopped.

• Replace export with captureExport(): play the song live (audible), tap the output losslessly via a ScriptProcessor, show a live "recording N%", and build a stereo WAV from the captured PCM (then lamejs -> MP3).

Verified: 4s song -> 1MB WAV / 117KB MP3, real audio.

▶ Play it: Food Court Eternity → Smoke Arithmetic → Barometric Stampede — a constellation across three families — the path is the mix https://stellate.app/?genre=vaporwave&seed=6623&path=1679.4415,292.16891,1718.20526&xdur=0.046

3f107eb https://github.com/aboard-io/stellate/commit/3f107eb76ac37ec4adef6e81aae7c368501153fb