add support for fetching loudness levels of audio streams

[bastiaanterhorst]

Description

This adds support for fetching loudness levels. This is used in Plexamp and Dash to show a waveform of the currently playing track. See here for a screenshot of what I mean.

Type of change

• New feature (non-breaking change which adds functionality)
• This change requires a documentation update

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have added or updated the docstring for new or existing methods
• I have added tests when applicable

I have not added tests (yet). Python is not my first language and I'm having a bit of trouble wrapping my head around how the test suite works.

[bastiaanterhorst]

Added a basic test that fetches a custom amount of levels and checks the returned list length.

[bastiaanterhorst]

@JonnyWong16 no interest in this patch?

[bastiaanterhorst]

Thanks for your review @JonnyWong16. I accepted your changes. Let me know if there is something else you'd like me to take a look at!

[JonnyWong16]

Please fix flake8 whitespaces.

https://github.com/pushingkarmaorg/python-plexapi/actions/runs/15974729408/job/45090440692?pr=1529

[bastiaanterhorst]

I fixed the whitespace issues

[bastiaanterhorst]

@JonnyWong16 I think you need to approve the workflows now?