Every headless test app built `GamePlugins`, whose `SoundPlugin` opened the default output device unless `$WOW_NOSOUND` or `$WOW_CAPTURE` was set, and no test run sets either. Under nextest that is one CoreAudio client and speaker stream per test process. With a few runs going at once, `coreaudiod` sat near 300% CPU, every sound on the machine crackled, and each test blocked on the audio server's connect.
A test build now takes the existing silent path, so its mixer is `None`, as with no device.
Test: `a_test_client_opens_no_audio_device`. With the change undone it fails on a machine with a speaker, taking 96 s; with it, the test passes in 0.06 s.
Fixes#2380🤖 Generated with [Claude Code](https://claude.com/claude-code)
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
(cherry picked from commit fbc90b9bbf272a784f3703eb0c68ea466fe90951)
# Conflicts:
# crates/benilla-app/src/game_plugins.rs
# docs/DEVIATIONS.md
Absorbed into the octo fork. The sound/mod.rs fix applies unchanged. Of the tests the conflict hunk carried, only this commit's own a_test_client_opens_no_audio_device is kept, retargeted from upstream's headless_client_unrun to our headless_client (same contract: every plugin's build runs, no schedule does); resource_writers and the_glue_preview_has_one_feeder come from other upstream commits and need glue_scene and GluePreview, which this fork has not got.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01SgstFWtn1RxEJ5kVrpgYwn
