* fix(distributed): stage sound detection audio
Sound detection passes frontend temporary paths directly to remote
workers, unlike transcription. Stage the WAV before classification so
CED can read it without a shared temporary directory.
Preserve the original request for retries and propagate staging errors
without calling the backend. Cover staging, request preservation, and
error handling with regression tests.
Assisted-by: Codex:GPT-6 golangci-lint
* test(distributed): verify routed sound staging
Call sound detection through the client returned by SmartRouter.Route.
This checks interface dispatch through both routing wrappers, rather
than constructing FileStagingClient directly.
The test fails without the sound-staging override and passes with it.
Assisted-by: Codex:GPT-6 golangci-lint
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Co-authored-by: Ettore Di Giacinto <mudler@localai.io>
