[Feature Request]: Fade in and fade out in audio

[KratozZ12]

I have:

• [✅ ] Searched if this feature hasn't been requested yet.
• [ ✅] Verified that I am using the latest version (run grep '"Version"' {~/.local,/usr}/share/plasma/wallpapers/luisbocanegra.smart.video.wallpaper.reborn/metadata.json or from Wallpaper settings > top right corner for version 1.0.0 and later), should be the same as https://github.com/luisbocanegra/plasma-smart-video-wallpaper-reborn/releases/latest

Install method used:

• [✅ ] Using Plasma's "Add new widget" (KDE Store)
• AUR
• Manually from the latest source code

Is your feature request related to a problem? Please describe.
I have a wallpaper that has sound and I like to use it with sound, but the sound just pops in and out, without any smooth transition

Describe the solution you'd like
Add a simple configuration for a "Fade in" and a "Fade out"

Describe alternatives you've considered
none

Additional context
none