- prevent drag-handle being clipped in header
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## Summary by CodeRabbit
* **Style**
* Reduced horizontal padding and header height in the app sidebar
fallback view for a more compact layout.
* Updated header padding in the workbench view and introduced
conditional left padding based on sidebar switch visibility.
* **Refactor**
* Simplified and centralized the logic for displaying the sidebar
switch, improving code clarity and maintainability.
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