Did a bit of refactoring to accomodate for later NativeAOT support:

• Each view & viewmodel has to be registered as a service
• Moved to source-generated JSON handling
• Hopefully, NativeAOT will make the app noticeably faster when I publish the project

Added global usings, and split up the project for better platform-specific service organization

Fixed the delete button not stopping the sound (how did I manage to fail that??)

Replaced the loop toggle with an Assign Shortcut button for quick access
I think the latter will be used more often, but having the loop toggle update two buttons at once was really cool

Sounds can now be added from YouTube; they are cached for fast access (how else would it work xd)
The window is not a dialog, so you can still interact with the soundboard while waiting for download(s)
(Idk if dialogs prevent interactions on some desktop environments tbh)
This is not the final layout, but it looks decent for now: clicking on a video (left side) takes you to the details page (right side) in the same window
Fun fact: pasting a youtube link automatically opens the video view, letting you download it even while the details are loading (will have to fix that up a little)