Implement system/desktop audio sharing on the Apple clients, feeding the
existing SCREEN_AUDIO Opus -> AEAD -> UDP path via vc_stream_feed_pcm. No
C++/protocol/codec changes -- the core was already ready (the Windows-only
loopback is #ifdef VOICECAT_HAS_LOOPBACK; off Windows the stream just waits
for fed PCM). Audio only; video is dropped.
macOS (in-process):
- ScreenAudioCapture.swift drives an audio-only SCStream
(excludesCurrentProcessAudio), converts Float32 -> int16 in the channel's
mono/stereo mode, and calls feedPcm. Capture starts on the self
.streamStarted event (effective config known then). Wired into
MainWindowController.screenAudioClicked().
iOS (forward-to-host, single session):
- VoiceCatBroadcast: a ReplayKit Broadcast Upload Extension consumes
.audioApp only, resamples to 48kHz int16 stereo (AVAudioConverter), and
writes a shared App Group SPSC ring (BroadcastAudioRing.swift). It does
not link libvoicecat.
- Host BroadcastAudioPump drains the ring (reacting to the extension's
Darwin notifications) and feeds the SCREEN_AUDIO stream it owns, downmixing
to mono when the channel is mono. Screen audio appears as a second stream
of the same user; no credentials persisted. UI is RPSystemBroadcastPicker
View in VoiceControlsView. Removes the speculative BroadcastCredentials.
Docs: voice.md s9, CLAUDE.md status, PROGRESS.md.
