feat(voice): add console audio IO and SessionHost audio routing

[toubatbrian]

Summary

Second PR in the series porting Python's TCP console session support to agents-js (follows #1693, the transport + updateIo plumbing). This adds the audio IO that lets a console-mode session exchange audio with a local broker (the LiveKit CLI lk session daemon).

• TcpAudioInput (agents/src/voice/console_io.ts) — resamples inbound audio_input frames from the 48 kHz wire rate to the 24 kHz agent rate and feeds them into the base AudioInput stream the STT pipeline reads from.
• TcpAudioOutput — resamples the agent's TTS frames back up to the wire rate, streams them as audio_output messages, and drives the flush/clear playout handshake: a flush blocks the agent turn until the broker reports audio_playback_finished, or reports an interruption (with a clamped playback position) when the buffer is cleared.
• SessionHost now accepts optional audioInput/audioOutput and routes inbound audio_input / audio_playback_finished messages to them in recvLoop.

Notes / divergences from the Python port

• Python's TcpAudioInput uses a stdlib queue + run_in_executor to bridge the producer and consumer event loops under JobExecutorType.THREAD. The JS console job runs in-process on a single event loop, so a StreamChannel is sufficient — no cross-thread queue.
• Time is tracked in milliseconds per the JS conventions; PlaybackFinishedEvent.playbackPosition is reported in seconds to match the base AudioOutput contract.
• The SessionHost audio fields are typed via import type from console_io.ts (the TS equivalent of Python's TYPE_CHECKING import) so there's no runtime import cycle.

Reference

Ports from Python livekit-agents cli/tcp_console.py (TcpAudioInput/TcpAudioOutput) and voice/remote_session.py (SessionHost._dispatch_transport_message).

Test plan

New agents/src/voice/console_io.test.ts (5 cases, all green):

• TcpAudioInput resamples 48 kHz wire frames to 24 kHz and exposes them on the stream
• TcpAudioInput drops frames pushed after close
• TcpAudioOutput streams resampled audio_output + audio_playback_flush, and the flush handshake completes (uninterrupted) on notifyPlayoutFinished
• TcpAudioOutput reports interruption (clamped position) when the buffer is cleared mid-playout
• SessionHost routes audio_input -> pushFrame and audio_playback_finished -> notifyPlayoutFinished

Also verified: pnpm build:agents, ESLint, and Prettier clean on the changed files. The existing room-based path is untouched.

Follow-up (next stacked PR)

• PR3: unregistered/console run path on the worker + JobContext fake-job support + CLI console subcommand wiring the transport + audio IO + SessionHost together.

[changeset-bot]

🦋 Changeset detected

Latest commit: 6bdfc5e

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 34 packages

Name	Type
@livekit/agents	Patch
@livekit/agents-plugin-anam	Patch
@livekit/agents-plugin-assemblyai	Patch
@livekit/agents-plugin-baseten	Patch
@livekit/agents-plugin-bey	Patch
@livekit/agents-plugin-cartesia	Patch
@livekit/agents-plugin-cerebras	Patch
@livekit/agents-plugin-deepgram	Patch
@livekit/agents-plugin-elevenlabs	Patch
@livekit/agents-plugin-fishaudio	Patch
@livekit/agents-plugin-google	Patch
@livekit/agents-plugin-hedra	Patch
@livekit/agents-plugin-hume	Patch
@livekit/agents-plugin-inworld	Patch
@livekit/agents-plugin-lemonslice	Patch
@livekit/agents-plugin-liveavatar	Patch
@livekit/agents-plugin-livekit	Patch
@livekit/agents-plugin-minimax	Patch
@livekit/agents-plugin-mistral	Patch
@livekit/agents-plugin-mistralai	Patch
@livekit/agents-plugin-neuphonic	Patch
@livekit/agents-plugin-openai	Patch
@livekit/agents-plugin-perplexity	Patch
@livekit/agents-plugin-phonic	Patch
@livekit/agents-plugin-resemble	Patch
@livekit/agents-plugin-rime	Patch
@livekit/agents-plugin-runway	Patch
@livekit/agents-plugin-sarvam	Patch
@livekit/agents-plugin-silero	Patch
@livekit/agents-plugin-soniox	Patch
@livekit/agents-plugin-tavus	Patch
@livekit/agents-plugins-test	Patch
@livekit/agents-plugin-trugen	Patch
@livekit/agents-plugin-xai	Patch

Not sure what this means? Click here to learn what changesets are.

Click here if you're a maintainer who wants to add another changeset to this PR