## Why
Audio queue saturation and processing delays could terminate voice sessions. Muted sessions also need outgoing audio to keep the peer alive.
## What changed
- Drop stale or excess incoming, capture, render-reference, and playback audio so fresh audio can resume. Reset affected processing state while preserving queue bounds and mute generations.
- Send paced, generated Opus silence while muted, without using device or processing buffers.
- Add fixed helper exit stages and session failure categories to default TUI logs without logging raw native errors, SDP, or device error text. Preserve observed helper exit status for shutdown.
## Testing
Extend tests to cover decoded mute silence and RTP sequence continuity, recovery after stale audio and queue saturation, and shutdown after observing helper output closure. Verify the helper's exit stage when the parent pipe closes during blocked startup.
GitOrigin-RevId: 17d580a72acd4423fb0b4f5107d9b541b964d069
Benjamin Carlsson
28f43b0417