Fix app volume tooltip and control in taskbar

[unchihugo]

Summary

Fixes bug when FluentFlyout starts and TaskbarWidgetScrollVolumeMode is set to 2, the taskbar hover tooltip lacks the app-volume percenntage text, and when scrolling, the app specific volume doesn't get modified until app restart, by clearing media player data cache for players with PID -1.

Type of Change

• Feature
• Bug fix
• Refactor (no functional changes)
• Style (formatting, naming)
• Other

Checklist

• Code changes are manually tested and working.
• Formatting and naming are consistent with the project.
• Self-review of changes is done.

• AI tools were used (if yes, I reviewed and fully understand the changes myself).