* fix: prevent idle watcher from unloading model during recording
the idle watcher treats ModelUnloadTimeout::Immediately as a 0s
timeout, causing idle_ms > 0 to always be true. this unloads the
model on the next 10s tick — even while the user is still recording.
the Immediately variant is already handled correctly by
maybe_unload_immediately() which fires after each transcription
completes. the idle watcher should skip it entirely.
fixes regression introduced in d1da935.
* fix race condition
* cleanup
* format
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Co-authored-by: CJ Pais <cj@cjpais.com>
095f4ac455