Ava: Fix nca extraction window never closing & minor cleanup (#4569)

* ava: Remove unused doWhileDeferred parameters

* ava: Minimally improve swkbd dialog

It's currently impossible to get the dialog to redirect focus to the InputBox.

* ava: Fix nca extraction dialog never closing

Also contains some minor cleanup

Ryujinx.Ava/UI/Applet/SwkbdAppletDialog.axaml

@@ -48,6 +48,7 @@
             Grid.Column="1"
             HorizontalAlignment="Stretch"
             VerticalAlignment="Center"
+            Focusable="True"
             KeyUp="Message_KeyUp"
             Text="{Binding Message}"
             TextInput="Message_TextInput"
@@ -61,4 +62,4 @@
             HorizontalAlignment="Stretch"
             TextWrapping="Wrap" />
     </Grid>
-</UserControl>
+</UserControl>