Prefs: Rewrite for GTK4

[tadfisher]

Rewrite preferences in GTK4. This may clobber some recent work done on other forks.

TODO:

• Retain scroll position when adding/removing shortcuts
  • Fixed by replacing TreeListModel with nested ListBox widgets
• Show shortcut conflicts (they are detected but not wired in to KeybindingsRow)
  • See screenshot below

Screenshots:

[mskorzhinskiy]

I have tested it a little bit (approx. one day) So far -- nothing to report. A lot of things are working, thank you very much for your work!

[jsravn]

Works for me as well. Nice job!

[michaelhthomas]

Odds are this will fix some of the weird keybinding issues as well. Looks great!

[mogenson]

I've noticed that this PR still gobbles the Super key and prevents it from being used with shortcuts outside of this extension (eg with Gnome desktop and Gnome shell).

For example, the following shortcuts do not work on Gnome 41.1, with the GTK4 preferences:

gsettings set org.gnome.shell.keybindings toggle-overview "<Super>Space"
gsettings set org.gnome.desktop.wm.keybindings switch-to-workspace-1 "<Super>1"

[tadfisher]

@mogenson Was this a problem with the current release? I didn't touch the actual shortcut-registering code.

[michaelhthomas]

@mogenson Was this a problem with the current release? I didn't touch the actual shortcut-registering code.

No, it has something to do with the code we merged in at the start of the fork. I'll have to take a crack at that at some point and see what's causing issues.