Update: Adapt tray icon to theme changes

[HO-COOH]

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This PR will utilize Community ToolKit's ThemeListener and update the tray icon to the correct light/dark mode in time. Unlike currently it only updates when there is a package update check, causing this

But the current ThemeListener does not work under WinUI3, and I have submitted another PR to them to get that fixed. I will mark this WIP with draft for now, and will switch the status to be ready once that PR gets merged.

[chris-tietgen]

I like this change. Is there a similar ticket to show the new updates available indicator on the taskbar icon?

[marticliment]

what do you mean?

[chris-tietgen]

I mean that the icon that displays on the taskbar doesn't show that green dot that appears on the icon in the tray area, so I can't tell at a glance that updates are available from that icon.

[marticliment]

I am afraid this is currently not possible, due to limitations with Windows AppSdk and Unpackaged apps