Keyboard focus navigation issues

[MewPurPur]

The inspector has no keyboard focus navigation by design, as there are plans to rework it. But there are other parts of the UI that should get keyboard focus navigation, but haven't yet.

High priority:

• The color picker can't be navigated fully (Note: This should be done with )
• The general layout can't be navigated fully
• Most of the settings menu can't be navigated

Low priority:

• Pressing Space in the custom file dialog triggers file actions even if the focus is elsewhere
• Directory navigation in the custom file dialog can't be used with keyboard
• In the custom file dialog, navigation the drives list automatically opens them
• The layout popup has no keyboard navigation
• The previews menu has no keyboard navigation
• The path actions popup has no keyboard navigation
• The transform list actions popup has no keyboard navigation