refactor(voice): Rewrite Voice Internals & DAVE Support (send & receive)

[DA-344]

Summary

Rewrites voice internals to have a cleaner, easier-to-maintain, voice implementation.

Adds support for DAVE connections.

Voice receive is currently broken

-> This code is partially inspired on discord.py's current voice implementation

Information

• This PR fixes an issue.
• This PR adds something new (e.g. new method or parameters).
• This PR is a breaking change (e.g. methods or parameters removed/renamed).
• This PR is not a code change (e.g. documentation, README, typehinting,
  examples, ...).

Checklist

• I have searched the open pull requests for duplicates.
• If code changes were made then they have been tested.
  • I have updated the documentation to reflect the changes.
• If type: ignore comments were used, a comment is also left explaining why.
• I have updated the changelog to include these changes.

Related

Fixes #2833

[nicokim]

Hey! I've been testing this branch for voice receive with DAVE and ran into some issues.

The audio coming out of the Sink is pretty much unintelligible, I attached an mp3 sample. Whisper (ASR) can't even detect the right language, it hallucinates Italian/English when I'm speaking Spanish lol

Some things I found while debugging:

• ~7% of packets throw OpusError: corrupted stream, but even the ones that "succeed" produce garbled PCM
• There's a double dave.decrypt() in _decode_packet (opus.py:728) — it decrypts the PCM bytes after Opus decode,
  but DAVE was already handled in decrypt_rtp(). That corrupts the audio
• PacketRouter._do_run doesn't catch OpusError, so one bad packet kills the receive thread
• stop_recording() in run()'s finally block can raise if recording already stopped

I know the PR says voice receive is broken, just wanted to share concrete findings in case it helps. Audio sample attached.

whisper_debug_1.mp3

[Lulalaby]

thanks for your comment. we are already aware tho and debugging it right now

[Lulalaby]

Handing over changes to #3143 as this PR includes unrelated changes from #2645.
Attribution has been made