feat(mpvpaper): add control center tile

[Yocraft-2000]

Summary

I added a control center tile to the mpvpaper plugin. Someone asked for it in the discord.

Motivation

Someone asked for it in the discord.

Type of Change

• Bug fix
• New feature
• Breaking change
• Refactoring
• Build / packaging

Related Issue

No github issue.

Testing

I added the tile to my control center and it opens the panel.

Manual Coverage

• Tested on Niri
• Tested on Hyprland
• Tested on Sway
• Tested on another compositor:
• Tested with different bar positions and density settings
• Tested at different interface scaling values
• Tested with multiple monitors

Screenshots / Videos

Checklist

• This PR is ready for review, or it is marked as Draft.
• I self-reviewed the changes.
• I added or updated translations/en.json, or this PR adds no new user-facing strings.
• I did not edit non-English translation files unless this PR is explicitly for translation tooling, an import/export sync, or a maintainer-requested locale change.

Additional Notes