[WIP] Add audio format conversion feature

[Codex]

Thanks for asking me to work on this. I will get started on it and keep this PR's description up to date as I form a plan and make progress.

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This section details on the original issue you should resolve

<issue_title>feat: Audio Format Conversion</issue_title>
<issue_description>Feature Request

Description
I would like to request a feature to support audio format conversion. Currently, the application lacks the ability to convert audio files between different formats. This feature would allow users to convert audio files from one format to another, such as .ogg to .mp3, .mp3 to .wav, and other common conversions. This is particularly useful for ensuring compatibility with different devices and applications that may not support all audio formats.

Platform(s)
Android, iOS.

Preferred Solution
The preferred solution is to integrate an audio processing library (such as FFmpeg or a similar robust library) that can handle various audio format conversions. The user interface should provide an option to select the input audio file, choose the desired output format, and then initiate the conversion process. The converted file should be saved in a user-specified location.

Alternatives
An alternative could be to use system-level audio conversion tools if available, but this would reduce cross-platform compatibility and add complexity for the user. Another alternative is to not implement this feature, but it limits the application's utility for users who need to work with different audio formats.

Additional Context
Common audio formats that should be supported include, but are not limited to:
MP3 (.mp3)
WAV (.wav)
OGG (.ogg)
AAC (.aac)
FLAC (.flac)
M4A (.m4a)

The conversion should maintain reasonable audio quality and, where possible, allow users to configure output bitrate or quality settings.</issue_description>

Comments on the Issue (you are @codex[agent] in this section)