Replace `Native` Player with `AVMediaPlayerProxy`

[JPKribs]

Summary

This issue serves as a parent issue for various AVKit issues & feature requests. It's been mentioned in a few locations, but the existing Native player will be removed in favor of consolidating all "players" into what is currently known as the Swiftfin player.

An AVMediaPlayerProxy has been created to service an AVPlayerLayer that is then used to render playback. This proxy needs to be finished, along with additional work for:

• PiP control with the video player
• Proper media track selection

Smaller fixes and changes to the Native player should still be acceptable as PRs. Larger changes or new features should avoid AVKit where possible. To avoid issues, please reach out with any questions prior to starting any new work around this topic!

Mentions:

#1826 (review)

#1581 (comment)

[JPKribs]

@LePips please feel free to edit this issue or remove if any of this information is incorrect. I'm going to use this issue to better group/set blockers.

[LePips]

I've edited the description to match what should be done.

[DrHurt]

@LePips @JPKribs

I'm really hoping the combined Swiftfin player would default to "AVPlayerLayer" for all supported media that can played directly or via a server-side remux (similar to how the web client works on iOS & macOS).

VLCKit can then be a fallback for unsupported codecs (where server-side transcoding is unavailable or unwanted).

VLCKit has audio sync issues with AirPlay speakers, lacks Atmos, HDR10+ & DV which will be a deal breaker for most Apple TV users. It also has occasional video stutters (likely not playing nice with TV motion processing).

Also power efficiency and battery life on iPhones & iPads is noticeably better with AVPlayer than VLCKit.