[Feature Req] Voice input support (via Amazon Transcribe?)

I have a demo use-case with a touchscreen but no keyboard, for which it'd be useful to support audio input.

I had a working prototype of this some time ago, but would need to clean up the code before being able to propose here directly. In general, it was along the lines of:
- Use the [`amazon-transcribe` Python SDK](https://github.com/awslabs/amazon-transcribe-streaming-sdk)
- Set up the transcription client in Chainlit's `@cl.on_audio_start` hook
- `send_audio_event` in Chainlit's `@cl.on_audio_chunk` hook
- `handle_events` in Chainlit's `@cl.on_audio_end` hook (I couldn't get this working in on_audio_chunk at the time on CL v2.6.2, because both the Chainlit hook and the Transcribe handler were async generators so didn't like being nested).

Start by locating the Chainlit @cl.on_audio_start, @cl.on_audio_chunk, and @cl.on_audio_end hooks described in the issue, then review the amazon-transcribe Python SDK flow. The work is complete when audio input is transcribed through Amazon Transcribe and integrated into the chat without the async-generator issue described for Chainlit v2.6.2.

Written by the indexing model from the issue text.