🐛 Compact NavigationPane just with toggle button or padding

[schwarda]

Describe the bug
First of all, NavigationPane has [toggleable] parameter but never used.
No combination of the current NavigationPane parameters will produce a compact pane that never opens and contains no toggle buttons or padding.

To Reproduce

Expected behavior
Setting the [toggleable] value to false should be enough to hide both the button and the padding.