Add functionality for Audio files on the API

## Suggested feature
- Route should be able to accept an audio file, convert it to text and answer with the `/chat/create` and `/chat/continue`.
- Another option would be to add the functionality into the existing routes

Look at the existing chat routes (`/chat/create` and `/chat/continue`) to understand the API structure. Research audio-to-text conversion libraries (like Whisper, Web Speech API) and how to integrate file uploads. Determine where to add the new route or modify existing ones, and test the end-to-end flow from audio upload to text response.

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