fix: pre-download BigVGAN vocoder to avoid GPU budget drain on MMAudio cold start

app.py

@@ -88,6 +88,12 @@ print("Pre-downloading AudioLDM2 (cvssp/audioldm2)…")
 snapshot_download(repo_id="cvssp/audioldm2")
 print("AudioLDM2 pre-downloaded.")
 
+# Pre-download MMAudio's BigVGAN vocoder (nvidia/bigvgan_v2_44khz_128band_512x, ~489MB).
+# This is fetched inside the GPU window on cold workers during MMAudio inference/regen.
+print("Pre-downloading BigVGAN vocoder (nvidia/bigvgan_v2_44khz_128band_512x)…")
+snapshot_download(repo_id="nvidia/bigvgan_v2_44khz_128band_512x")
+print("BigVGAN vocoder pre-downloaded.")
+
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