feat: add Fish Audio TTS support

[twangodev]

Description

This adds support for fish.audio as a cheaper alternative to Elevenlabs. You can also use any voice (clone it from fish.audio)

I also removed the explicit specification for nvenc for ffmpeg - I can restore the changes if needed but it was just to get the project to work on my machine - #2259 might be relevant

Issue Fixes

None

Checklist:

• I am pushing changes to the develop branch
• I am using the recommended development environment
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have formatted and linted my code using python-black and pylint (the other files fail, I assume we can format in a later commit)
• I have cleaned up unnecessary files
• My changes generate no new warnings
• My changes follow the existing code-style
• My changes are relevant to the project

Any other information (e.g how to test the changes)

None

[JasonLovesDoggo]

Thank you for the contributions! Best of luck over @ Fish!