preResolveAudio abstract method
Materializes every audio source in sources into a sandbox file the
encoder can -i, validating and allowlisting each one first.
Runs in the pre-resolve pass before the frame loop and is idempotent: a
source already materialized is skipped. A disallowed network host is a
FluvieRenderException naming the host, surfaced here before any fetch —
audio mixing happens entirely in the encoder, never in capture, so no
frame ever awaits audio. The reactive analysis the same source feeds (the
beat grid and band table) is handled by preResolveReactive.
Implementation
Future<void> preResolveAudio(Iterable<AudioSource> sources);