Chardonnay UI bug fixes and improvements

- Theme changes do not require restart
- Fix some text appearing black in dark mode
- Fix dialog boxes not appearing correctly on Windows
- Fix queue vertical scroll bar overlapping items

Source/LibationAvalonia/Dialogs/SearchSyntaxDialog.axaml.cs

@@ -12,8 +12,6 @@ namespace LibationAvalonia.Dialogs
 		{
 			InitializeComponent();
 
-			this.HideMinMaxBtns();
-
 			StringFields = @"
 Search for wizard of oz:
      title:oz