[IMPROVEMENT] (Separate setting for tray icon)

### Please confirm these before moving forward.

- [x] I have searched for my feature proposal and have not found a work-in-progress/duplicate/resolved/discarded issue.
- [x] This improvement refers to an existing feature. If you want to suggest a new feature, please use [this template](https://github.com/marticliment/WingetUI/issues/new?assignees=marticliment&labels=new-feature&projects=&template=feature-request.yml&title=%5BFEATURE+REQUEST%5D+%28Enter+your+description+here%29).
- [x] This improvement is not a bug. If you want to report a bug, please use [this template](https://github.com/marticliment/WingetUI/issues/new?assignees=marticliment&labels=bug&projects=&template=bug-issue.yml&title=%5BBUG%5D+%28Enter+your+description+here%29).

### Describe the improvement

Please, add the feature "Tray icon theme" in order to separate it from the existing feature "Application theme".

### Describe how this improvement could help users

It will be useful because the feature "Application theme" changes colour of the app GUI and tray icon simultaneously now.
It will be useful if user wants to change Windows taskbar colour and tray icon colour and tray icon must stay visible on taskbar.
If user doesn't want to change app GUI colour - only tray icon colour - he can do that with the feature described.