Monitor GTK4 port

[stsdc]

Note: Indicator build is disabled for now. Waiting for Wingpanel GTK4 port to finish.
Note: Deprecation warnings connected to TreeView, TreeIter, TreeViewColumn, CellRendererPixbuf are out of scope for this PR.

To Fix:

• ProcessInfoView not showing
• ProcessInfoView graphs and file list not showing
• Restore button_more_info
• Search box loosing focus after 1-2 character input
• SystemView bad layout
• Some labels are now invisible due to wrong colour (stylesheet problem?)
• Fix statusbar labels
• Merge LabelRoundy
• Memory usage of pid's window (Wnck port) (removed -- I don't see that it is used in other apps)
• The graph on CPU chart should be in background and not covering the labels. Other charts are probably affected too
• Fix GLib-GObject-CRITICAL's

[stsdc]

Looks like sidebar is not showing up on main nor on this branch anymore.

[stsdc]

Looks like ctrl-e and ctrl-k not working

[danirabbit]

I'm seeing the sidebar on both here?

[danirabbit]

Still don't love adding CSS changes here, but overall I think this is okay and we can continue to iterate in main :)

[stsdc]

Can't rebase - still has conflicts 🤨
Shell we use squash & merge?

[danirabbit]

@stsdc yes I would definitely recommend squash merge in the web UI over trying to manually rebase this

[stsdc]

Yeah, I had to fix alignment and height, since SystemStorageView doesn't use WidgetResource.

[danirabbit]

Builds in CI, so lets' go 🚀