MainWindow: use Adw.ToolbarView

[danirabbit]

So we can easily switch styles per view

[stsdc]

I have an issue with this because on the process view the topbar has the bottom border visible, but on the System view it disappears. From my perspective it is better to have the same style on both views. Are we going to miss anything besides styles, if we will not switch to Adw.ToolbarView?

[danirabbit]

@stsdc I did that on purpose because otherwise you have separators going into nowhere:

And on the process view, the shadow shows when you scroll:

[stsdc]

Understood.
Can we have the separator on both views? Or add the bottom border 1px grey solid to the Headerbar?

NGL SystemView looks much cleaner, but it is inconsistent with the ProcessView.

[danirabbit]

@stsdc done :)

[stsdc]

@danirabbit thank you!