That looks like it checks most of my boxes, but I have a personal/philosophical objection to running a service. The objection is, I don't want to[0]. I just want a local application. Not local-first, I want local-only. Just an application.
[0] and also I think it's insane to add that much complexity to something that is single-user.
I'm also a navidrome user and I run it via docker exposed via traefik so I can access my music anywhere. I can use any subsonic client on android or iOS and I can bluetooth that to my car or headphones or whatever and I can load it up on my laptop anywhere.
As you've said you just want a local application just wanted to mention that in case that's actually something that might also be useful for you.
Totally understandable. I recently thought of developing a cross platform player in C# and AvaloniaUI, but cross platform audio is not as easy as it seems, especially trying to use open source libs only and minimizing dependencies.
[0] and also I think it's insane to add that much complexity to something that is single-user.