feat(assemblyai): add u3 context options

[rosetta-livekit-bot]

Summary

• add AssemblyAI u3-rt-pro-beta-1 as a streaming STT model option
• add agentContext and previousContextNTurns options and forward them with AssemblyAI wire keys
• treat u3-rt-pro and u3-rt-pro-beta-1 as the same model family for validation and defaults

Tests

• pnpm --filter @livekit/agents-plugin-assemblyai lint
• pnpm --filter @livekit/agents-plugin-assemblyai... build
• pnpm --filter @livekit/agents-plugin-assemblyai build
• pnpm vitest run plugins/assemblyai/src/stt.test.ts

---

Ported from livekit/agents#6017

Original PR description

Summary

• agent_context: new streaming parameter (Universal-3 Pro only, mid-stream updatable via update_options and sent as an UpdateConfiguration message over the live websocket). Set at construction or per turn; max ~1500 chars.
• previous_context_n_turns: new connect-time parameter (Universal-3 Pro only) controlling how many prior finalized conversation entries are carried forward as context. 0 disables carryover; unset uses the server default.
• u3-rt-pro-beta-1: new model option that shares u3-rt-pro behavior; generalizes the u3-pro-only parameter gating to the u3-rt-pro family.

Note: an earlier revision of this PR included an enable_agent_context(session) convenience helper that fed each agent turn into agent_context. That has been deferred to a follow-up exploring a cleaner UX — an STT enable_agent_context=True flag with framework support (including LiveKit Inference). The agent_context parameter itself remains here and can be set at construction or via update_options().

Test Plan

• uv run pytest --plugin assemblyai — 37 tests (field plumbing, websocket UpdateConfiguration, connect config, u3-rt-pro family gating)
• ruff format + lint + mypy clean on touched files

[changeset-bot]

🦋 Changeset detected

Latest commit: 922325a

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-plugin-assemblyai	Patch
@livekit/agents	Patch
@livekit/agents-plugin-anam	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-plugin-trugen	Patch
@livekit/agents-plugin-xai	Patch
@livekit/agents-plugins-test	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.