fixes #23881

Isidorn/action items lifecycle fixes #23822

- Implement APIs in ResolvedKeybinding to expose parts
- Implement APIs in ResolvedKeybinding to get labels without modifiers
- Adopt tests to above API changes
- Use above APIs to search and highlight keybindings
- A new keybinding label widget to render a keybinding
- Adopt above widget in Keyboard shortcuts editor and define keybinding widget