[BUG] A song with no album cover retains the previous song's album cover

Submission checklist

• I have searched existing issues and confirmed this is not a duplicate.
• I am using the latest available version of Noctalia.

Bug description

If you are listening to a song with album art metadata (song A) and then start listening to a song with no album art metadata (song B), the media player shows the album art of song A rather than nothing (which is what's displayed if there's nothing playing before starting song B)

https://github.com/user-attachments/assets/74a542d2-b631-4562-9821-4e1b97df7d35

Steps to reproduce

1. Play a song with album art metadata
2. Skip to a song without album art metadata
3. Behold the incorrect album cover

Expected behavior

When there's nothing playing before starting a song without album art metadata, there is nothing displayed in the album art section of the media player.

Actual behavior

The album art of the previous song is displayed, which often doesn't match the current song

Logs / error output

Nothing is printed out when this occurs

Noctalia version

v5.1.0 8c52cb71b5bcafbf67bfb8e659f1fc45f882a008

Compositor

Umbriel

Distribution

NixOS

Environment information

Installation method: Nix flake (binary downloaded from cachix)
GPU: Nvidia GeForce RTX 3070

Additional context

Using Kopuz as the actual music player here, playing from a local library of mp3 files