livekit-agents@1.3.9

## What's Changed
* chore(xai): update voice names according to docs by @davidzhao in https://github.com/livekit/agents/pull/4295
* Add local dev commands for linking to rtc-sdk by @lukasIO in https://github.com/livekit/agents/pull/4258
* Ensure makefile checks for livekit_lib_path by @lukasIO in https://github.com/livekit/agents/pull/4298
* feat(gemini3) : Add Gemini 3 support with thinking_level and thought_signature by @varghesepaul in https://github.com/livekit/agents/pull/4027
* fix list mutation during iteration by @theomonnom in https://github.com/livekit/agents/pull/4304
* add gemini 3 flash model by @tinalenguyen in https://github.com/livekit/agents/pull/4301
* Websockets improvement by @cshape in https://github.com/livekit/agents/pull/4303
* Allow for Cartesia TTS language auto-detection by @yuyuma in https://github.com/livekit/agents/pull/4300
* Add Amazon Nova 2.0 Sonic Support with Text Input and Enhanced Features by @kachenjr in https://github.com/livekit/agents/pull/4176
* fix dynamic FieldInfo for pydantic 2.12 by @longcw in https://github.com/livekit/agents/pull/4290
* re-export TurnDetection for xAI by @tinalenguyen in https://github.com/livekit/agents/pull/4306
* fix commit_user_turn when last_final_transcript_time is None by @longcw in https://github.com/livekit/agents/pull/4308
* feat(soniox): add language_hints_strict option for STT by @cateet in https://github.com/livekit/agents/pull/4281
* feat(google-tts): add prompt to normal synthesize for Gemini TTS by @NXV5111 in https://github.com/livekit/agents/pull/4208
* Adding extra content to OpenAI LLM. Improving function call grouping. by @russellmartin-livekit in https://github.com/livekit/agents/pull/4170
* feat(gemini3) use low latency thinking_level by default for gemini 3 models by @pushkar-nurix in https://github.com/livekit/agents/pull/4311
* fix handoff to Realtime model with existing session context by @davidzhao in https://github.com/livekit/agents/pull/4310
* tts metrics update by @dhruvladia-sarvam in https://github.com/livekit/agents/pull/4117
* AGT-2302: add aligned_transcript to STT by @chenghao-mou in https://github.com/livekit/agents/pull/4155
* Minor readme doc fixes by @kachenjr in https://github.com/livekit/agents/pull/4320
* vad enabled by @dhruvladia-sarvam in https://github.com/livekit/agents/pull/4321
* handle exceptions in task_results by @tinalenguyen in https://github.com/livekit/agents/pull/4323
* add `livekit-durable` functions by @theomonnom in https://github.com/livekit/agents/pull/4272
* fix py3.10-py3.12 &`livekit-durable` cibw by @theomonnom in https://github.com/livekit/agents/pull/4324
* stringify cartesia error to be pickleable by @tinalenguyen in https://github.com/livekit/agents/pull/4328
* livekit-agents 1.3.9 by @theomonnom in https://github.com/livekit/agents/pull/4329

## New Contributors
* @varghesepaul made their first contribution in https://github.com/livekit/agents/pull/4027
* @NXV5111 made their first contribution in https://github.com/livekit/agents/pull/4208
* @russellmartin-livekit made their first contribution in https://github.com/livekit/agents/pull/4170
* @dhruvladia-sarvam made their first contribution in https://github.com/livekit/agents/pull/4117

**Full Changelog**: https://github.com/livekit/agents/compare/livekit-agents@1.3.8...livekit-agents@1.3.9