Implement WinUI-style immersive overlays and migrate existing pop-ups; tweak context menus to better match WinUI styling; implement sliding pill animation

[Meteoni-San (Meteony)]

Replaces pop-up windows with same-window immersive dialogs styled after WinUI.
The PR also:

• improves caption button styling (minimize, maximize, close with changed glyphs, taller Windows11-style designs, and proper colors)
• adjusts context menus (right-click, tray and main menu overflow menu) to be more similar to WinUI
• introduces small refinements for the UI interface in various places (glitchy pill with expansion menu open, new darker WinUI-accurate dark mode fallback color, etc.).

Closes: #5189, #5191, #5177

[Meteoni-San (Meteony)]

Gabriel Dufresne (@GabrielDuf) Hi! Could you take a look at this when you get time? Thanks!

[Gabriel Dufresne (GabrielDuf)]

Hi,

Before I can properly review this, would it be possible to make the branch available in a way that I can check out locally? I'm able to view the PR and your fork on GitHub, but I haven't been able to clone or check out the branch to test the changes, as I get an "Access denied" error.

Also, while I don't mind the underlying fixes, I'd prefer to keep the current layout of the operation/package details panel. I understand the goal is to make it look more like WinUI, but the current layout was intentionally designed to resemble the UI that existed before the migration to Avalonia, and I'd like to preserve that.

I don't mind keeping the immersive dialogs; it's mainly the changes to the rest of the layout that I'd prefer to avoid. I'd appreciate it if you could keep the existing layout and limit this PR to the functional changes. If you'd like to propose a redesign of this view, I'd be happy to discuss it in a separate PR.

[Meteoni-San (Meteony)]

Hi,

Before I can properly review this, would it be possible to make the branch available in a way that I can check out locally? I'm able to view the PR and your fork on GitHub, but I haven't been able to clone or check out the branch to test the changes, as I get an "Access denied" error.

Also, while I don't mind the underlying fixes, I'd prefer to keep the current layout of the operation/package details panel. I understand the goal is to make it look more like WinUI, but the current layout was intentionally designed to resemble the UI that existed before the migration to Avalonia, and I'd like to preserve that.

I don't mind keeping the immersive dialogs; it's mainly the changes to the rest of the layout that I'd prefer to avoid. I'd appreciate it if you could keep the existing layout and limit this PR to the functional changes. If you'd like to propose a redesign of this view, I'd be happy to discuss it in a separate PR.

I'm not sure about the access issue you mentioned. My fork repository should be public and checking out shouldn't be an issue. I'll look into it in a bit.

For issue 2 specifically: keeping it pixel-perfect to the previous UI is also my goal as well. I had the original WinUI version open side-by-side during testing, and the effect is very similar to the one I implemented.
Every UI change here is for accuracy towards the previous UI, including the change to the context menus, or the inactive backdrop color, or the sliding pill indicator, which all of those existed before, were lost during the rewrite, and are now checked against the previous UI before the migration.
I don't quite see the point of splitting out this PR, which would be too slow and difficult to do. However, if there's something that you'd like to change also due to the sake of accuracy, we can discuss it right here.
You can basically ask me to defend my case for every change, and I'll either revise the approach or produce the matching screenshot comparisons.

You can find my own debug builds here:
https://github.com/Meteony/UniGetUI/actions/runs/30185906971/job/89750460329

[Meteoni-San (Meteony)]

Hi,

Before I can properly review this, would it be possible to make the branch available in a way that I can check out locally? I'm able to view the PR and your fork on GitHub, but I haven't been able to clone or check out the branch to test the changes, as I get an "Access denied" error.

Also, while I don't mind the underlying fixes, I'd prefer to keep the current layout of the operation/package details panel. I understand the goal is to make it look more like WinUI, but the current layout was intentionally designed to resemble the UI that existed before the migration to Avalonia, and I'd like to preserve that.

I don't mind keeping the immersive dialogs; it's mainly the changes to the rest of the layout that I'd prefer to avoid. I'd appreciate it if you could keep the existing layout and limit this PR to the functional changes. If you'd like to propose a redesign of this view, I'd be happy to discuss it in a separate PR.

Hi,

I checked the repository and the branch is public and still available. I suspect the checkout problem may be caused by the PR branch being named main, since that can conflict with the existing local main branch.

You should be able to check out the PR without accessing my fork directly using GitHub’s PR ref:

git fetch origin refs/pull/5194/head:pr-5194
git switch pr-5194

Please let me know the full command and error output if this still fails.

[Gabriel Dufresne (GabrielDuf)]

Hi Meteoni-San (@Meteony), I took a look at the PR, and the dialog migration itself looks great.

There are two things that need to be addressed before this can be merged:

• This PR removes "by Devolutions" from the version string in two places:

  • SidebarViewModel.cs:125 — sidebar footer version label
  • TrayService.cs:139 — system tray menu version item

  Both change "UniGetUI Version {0} by Devolutions" to "UniGetUI Version {0}".

  The "by Devolutions" branding needs to stay. This is non-negotiable for us, so please revert those two changes.

• I also noticed an animation issue with the navigation selection pill. For example, when moving from Discover Packages to Package Managers, the pill briefly expands vertically and becomes much taller than it should before settling into place. It only lasts a fraction of a second, but I don't think that's the intended behavior. Could you take a look at that as well?

Other than those two points, everything else looks good. Thanks!

[Gabriel Dufresne (GabrielDuf)]

the selection pill: