fix(voice): ignore markup tags for transcript pacing

[rosetta-livekit-bot]

Summary

• pace synchronized transcripts using visible text with expressive markup stripped
• keep forwarding raw text so downstream transcript outputs can strip/surface markup as before
• add the source-equivalent regression for markup fragments adding no pacing delay

Testing

• pnpm exec prettier --check agents/src/voice/transcription/synchronizer.ts agents/src/voice/transcription/synchronizer.test.ts .changeset/markup-pacing-tags.md
• pnpm vitest run agents/src/voice/transcription/synchronizer.test.ts
• pnpm build:agents
• cue-cli runtime validation with temporary voice agent: agent_state_changed(.new_state="AS_SPEAKING") -> conversation_item_added(.item.message.role="ASSISTANT")[30s]

---

Ported from livekit/agents#6350

Original PR description

A markup tag with spaces in its attributes (e.g. Inworld's ) is split across word tokens by the synchronizer's word stream, so the per-token split_all_markup() never saw a complete tag and paced every fragment as if it were spoken — delaying the transcript ~3-4s per expressive sentence, compounding over the turn.

Give each segment a stateful TranscriptMarkupStripper (already used by the room output for the same cross-chunk problem) so tag fragments are held until the tag completes and contribute zero hyphens to pacing. Raw tokens are still forwarded unchanged for downstream stripping and lk.expression extraction.

[changeset-bot]

🦋 Changeset detected

Latest commit: 3ae70d7

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

This PR includes changesets to release 36 packages

Name	Type
@livekit/agents	Patch
@livekit/agents-plugin-anam	Patch
@livekit/agents-plugin-anthropic	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-did	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

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[devin-ai-integration]

✅ Devin Review: No Issues Found

Devin Review analyzed this PR and found no bugs or issues to report.